The Green Walls Column
Hydroponic Living Walls – DIY – Really?
By George Irwin, The Green Wall Editor
February 10, 2012
Over the years I haven’t done a particularly good job writing about hydroponic based technology, more specifically hydroponic green walls. I would contribute that to the fact that beyond the work of the ever popular Patrick Blanc, the technology was still being developed for vertical walls.
I personally have found them a cumbersome maintenance project; however there have been advances in materials and easy applications, but not without a “fine line” between success and failure. I’m going to share some of my experiences and explain that “fine line” that includes some detailed variables.
Patrick Blanc's latest works in Berlin, Germany
at the Düssman das KulturKaufhaus, 2011.
Like green walls in general, hydroponic techniques are not new; the Greek term “Hydro” means water and “Ponos” is labor. Even the gardens of Babylon had a pumping system to bring water to the top of the garden, letting it trickle back down to the lower pools.
Nature irrigates naturally occurring walls through runoff that collects nutrients from natural decomposition to feed the plants clinging to the sides of cliffs and other rock walls. In a previous article (The Original Green Living Wall: Basis for Great Design, September 26, 2010), I described the origin of green walls and the natural rock faces created by Mother Nature. Nutrients and minerals are created naturally, picked up by runoff as the roots are bathed in a nutrient rich solution. Sounds simple to recreate, right? Not so fast! We’re talking about Mother Nature here.
I have documented and studied naturally occurring green walls over the years. Since I live in upstate New York (USA), I am much more familiar with the local native plant types except for my time spent outside of Portland, Oregon hiking to Multnomah, Latourell, Wahkeena and Horsetail waterfalls along the Columbia River.
The walls I have studied here are the epitome of “Native Living Walls.”
Living wall by Mother Nature along the Larch Mountain trail OR, consisting of native plants including various lichen & ferns.
Before I continue let me make reference to the nomenclature of “Green Walls” as a general term, which is divided into “Green Facades” and “Living Walls.” Since living walls are defined by having the root system throughout the wall, naturally occurring green walls are defined as living walls.
A green façade is usually a 3d trellis like support structure with a climbing plant found at the base. In nature climbing plants are also naturally occurring however for the purpose of this article our focus is living walls.
Although my hiking has decreased to almost none over the past year due to knee surgeries, I still feel that naturally occurring living walls provide a spectacle only found in nature. Plants we see as common or to the untrained eye might seem like nothing more than moss and ferns. A close look displays an awesome range of colors and textures; to the touch on a hot summer day the walls are cooling and provide a haven for animals and insects of all kinds. Every wall I have seen up-close has contained a variety of liverworts, ferns, mushrooms, lichens and wild flowers.
Left to Right:
Anomodon attenuatus (anomodon moss),
Atrichum undulatum (undulate atrichum moss).
Left to Right:
Dicranum fulvum (dicranum moss), Asplenium scolopendrium (Hart's-tongue fern) - this fern is on the New York State Threatened List and the majority of these can be found in New York State.
The pictures provide just a small sample of what can be found growing on the natural living walls. Without the use of synthetic fertilizers, this is natural hydroponics at its best.
Left, Right and Below:
Aquilegia canadensis (wild columbine), Ilex verticillata (American winterberry), and Sedum spathulifolium ('Cape Blanco' stonecrop).
This Sedum from Oregon is a favorite food for the pika (a small relation to the rabbit). In the spring look for a bright yellow flower that stands out against the lichen.
Trying to duplicate Mother Nature’s efforts is no easy task. In nature plants adapt and are conducive to the environment; they are naturally at home.
Installing a hydroponic living wall is relatively easy; the challenge is to meet all the needs of a plant pallet that is part of the man made ecosystem - totally unnatural and more times than not combining plants that are not of the same needs is the main reason for failures.
Hydroponic living walls are also much different than the traditional horizontal technology developed to grow food. For starters, the living walls are vertical unlike food producing units that are horizontal, even if they are “stacked” as towers and allow the vegetation to climb vertical (Green Façade).
Before we talk about the DIY materials and “How To” part, let’s start with the types of hydroponic systems available. There are active and passive hydroponic systems, easily remembered because “active” means with a mechanical pump (which is the common for hydroponic living walls). In an active system, moving water is infused with chemical nutrients as it passes over the roots. A passive system works without a pump and utilizes a wicking fabric or some type of inorganic media that that draws water to the roots. The green wall systems I have had the opportunity to trial and work with have a combination of materials, everything from felt, to cleaning scrub pads (mineral wool), plastic, poly vinyl chloride (PVC) and coco husk, and they all rely on a mechanical means (active system).
I have not found one single combination of products and techniques that make hydroponic green walls a foolproof method. Some are much more successful than others but not without attention to detail and intensive maintenance requirements. In a natural occurring living wall the plants that are native to the surroundings are adapted to the conditions. “Conditions” refer to elevation, lighting, nutrient availability and in nature only plants that are adapted to the present conditions will continue to thrive. In the living wall the task of plant survival is put on the installer, system type and the expertise of the maintenance technician. Just because you are a landscaper or interior plant company, don’t assume you’re going to be able to jump right in and master hydroponic living walls - there is a learning curve.
I do have relationships in the industry, some of them with national companies; they maintain both media /soil based walls and other hydroponic walls. The maintenance on the hydroponic walls is a break-even scenario for them because of the higher than average maintenance needs. The variables and conditions are ever changing and having the ability to meet the maintenance needs and upkeep is an education only experience can bring.
Here is that “fine line” between success and failure. Many variables are under constant monitoring in order to be successful. Hydroponic living walls are seldom 100% lush and thriving all the time because of the ever changing variables with very little room for error. Even a slight change in temperature can disrupt the dynamics of the wall causing massive areas of die-off; we will talk more on monitoring the walls later.
Hydroponic Living Wall: Basics
Hydroponics require many variables to come together in sync in order to be successful. My own reading suggests that experience and education are a must before diving into hydroponic growing. For the most part, common landscapers and indoor plant companies are usually not at the level of expertise when they decide to either install or take on the maintenance of a hydroponic living wall. Medias / root support structures, clean water, temperatures, pH levels, lighting, nutrient solutions, and oxygen exchange (oxygen to nutrient ratios), are part of the synchronization of successful hydroponic walls.
Hydroponic living walls start with some type of waterproofing to protect the structure behind the wall. There are common water proofing membranes, peel and stick applications, PVC sheets or in some cases I have seen layers of felt stapled directly to a concrete wall.
Felt fabrics, coco husk and porous sheets of scrub pads (mineral or rock wool) and porous foam are the most popular types of rooting media materials. There are many varieties of applications for each of these products – again, I’m not partial to one particular material and I have seen various results with some better than others.
Left to Right: hydroponic capillary mat; felt fabric; capillary fabric with plastic lining and geo-textile backing (manufacturers unknown); http://www.therange.co.uk.
Deciding on what fabric or media to use can only come through experience. Personally I have documented and found high amounts of root and crown rot in all the media types shown here.
Left: 3M Doodlebug close up, 56” wide, by 42 yards long @ $32 per yard; purchase information contact: Joe Koszarek, Beacon Lighthouse Inc.; firstname.lastname@example.org. Right: Nedlaw Hydroponic Living Wall constructed from two layers of similar 3M Doodlebug scrub pads in larger rolls prior to being cut.
Coco husk block inserted into a geo-textile bag by GSky.
Left: Polyester weave (manufacturer unknown); Right: open cell polymer foam blocks similar use by Eco-Walls; purchase information contact: Chi Meng http://www.chimeng.com.tw
Avoiding Root Rot & Other Potential Issues
According to Wikipedia, "In hydroponic systems inside greenhouses, where extensive monocultures of plants are maintained in plant nutrient solution (containing nitrogen, potassium, phosphate, and micronutrients) that is continuously recirculated to the crop, Pythium spp. cause extensive and devastating root rot and is often difficult to prevent or control."
Root rot can occur in hydroponic applications, if the water is not properly aerated. The root rot affects entire operations within two to four days due to the inherent nature of hydroponic systems where roots are nakedly exposed to the water medium, in which the zoospores can move freely. (http://en.wikipedia.org/wiki/Pythium)
Hydroponic living wall showing signs of both crown and root rot.
Symptoms include leaf drop, yellowing & discoloration.
It is typical that root rot is the result of an anaerobic environment. (As we continue I will explain the importance of balancing nutrients and oxygen exchange.)
Root rot evident sandwiched between two layers of 3M Doodlebug.
Distinct onset of root rot, this particular plant will last another 24-72 hours.
Other factors include: unsterilized tools and equipment, unfiltered water, dead roots and leaves, other infected plant material. As a former landscape contractor I know personally what it would take to sterilize my tools to work on such a wall - frankly, it may be too much trouble.
This is one of the reasons the cost of maintenance is high. The preventative labor is equal to the actual labor pruning and replacing of plants.
||Hydroponic Living Wall utilizing open cell foam showing plant loss due to crown and root rot.|
||Obvious signs of yellow and discolored leaves, leaf loss and plant deterioration.|
||This hydroponic living wall shows a variety of symptoms that include: Root rot, discoloration, crown rot and algae build up. If you look closely you will see some naturally formed lichen and the burnt tips of the leaves that may be caused by salt build up or over fertilizing. |
Because of the constant presence of water, hydroponic living wall media can become a breeding ground for algae and gnats. Keeping the plants healthy, vigorous and stress-free is the best "cure" against Pythium. Pythium is almost impossible to 100% eradicate from an infected system; this involves starting completely over with new plants, containers, equipment, etc.
To remedy the wall you will have to disinfect the entire system. Manual scrubbing and bleach might be necessary, adding tap water, and disinfecting the water with strong hydrogen peroxide (H2O2). The solution will require 100ppm to kill pythium - however, this can also kill small plants. Wait 24 hours for H2O2 to dissipate to a safe level; do not add more water to system!
Add only H2O2-treated water, add nutrients and beneficial enzymes. The aerobic-loving enzymes will colonize the sterilized medium and system, hopefully displacing any of the anaerobic bacteria. Starting with a clean system is the best prevention.
Below you can see leaf build up at the drain (right) and fallen leaves rotting on the left. These dead leaves become food for the Pythium. This is also true with algae. Algae will eventually dry, die and become organic material, fueling Pythium fungus. Once started it becomes a vicious cycle without sterilizing the entire wall. There are chemical / biological preventatives; I would suggest going to talk with your local hydroponic store.
Left: Leaf build up; Right: Rotting leaves.
Once you decide on a rooting media, having clean water is not an option. Some professional growers will use distilled water and this is much more expensive; however, hydroponics are very sensitive to salts, pH and changing variables including temperature. The water is a vehicle that transports a nutrient solution to the top of the wall via a pumping system and allows it to saturate the rooting media via gravity from the top down while bathing the roots.
All plants need key macronutrients: Nitrogen, Phosphorus and Potassium lead the list of “must have” chemicals:
Nitrogen (N) —promotes vegetative growth
Phosphorus (P)—contributes to healthy roots and flower blooms
Potassium (K)—important to fight off disease and resistance to pests
Sulfur (S)—health and improved color of the leaves
Calcium (Ca)—promotes new root growth
Magnesium (Mg) chlorophyll—contains a Mg ion that improves food production
In commercial fertilizers the N, P & K are depicted by numbers in ratio to the weight of each one. For example 10-10-10 is a balanced ratio of N, P & K. In contrast, 25-5-5 will provide a quick rapid greening of the visual leafy portion of the plant with only 1/5th the P & K. Boron (B), copper (Cu), cobalt (Co), iron (Fe) manganese (Mn), molybdenum (Mo), and zinc (Zn) are micronutrients responsible for a myriad of tasks including: cell wall development, nitrogen and sugar metabolism, protein synthesis and water loss just to name a few.
Vegetation acquires these micronutrients directly from natural growing media; commercial producers of fertilizer do not include them for typical landscape and crop applications, but because the hydroponic technologies for living walls do not include a growing media that can hold nutrients, the nutrient solution MUST include these essential micronutrients.
This is where inexperience becomes costly. If you are not trained nor have experience with vegetation for hydroponic living walls, the risk may outweigh the glory. This is not a project you want to experiment with a client. You risk reputation and serious monetary loss simply through maintenance and plant replacement. I mentioned earlier we work with a very experienced indoor plant company who is happy to break even on the maintenance of the hydroponic living walls they maintain. They keep the wall as part of the overall maintenance account for the building. There are many over the counter pre mixed nutrient solutions available; contact your local hydroponic supplier for more details.
(For an interesting debate on Organic vs. Hydroponic Growing, visit Jungle Walls by Peter Kastan.)
Once you add plants, the variables will continue to grow from here, no pun of course. You have to find a balance between nutrient solutions, pH levels, temperatures, lighting, and dissolved oxygen. All of these variables must be in alignment for a hydroponic living wall to work.
pH is a scale from 1 to 14 that measures acid-to-alkaline balance: 1 being the most acidic, 7 is neutral and 14 is most alkaline. Every full point change in pH represents a 10-time increase or decrease in acidity or alkalinity. For example, soil or water with a pH of 5 is 10 times more acidic than water or soil with a pH of 6. Water with a pH of 5 is 100 times more acidic than water with a pH of 7. With a 10-fold difference between each point on the scale, accurate measurement and control is essential to a strong, healthy garden.
Most plants grow best with a pH between 6.5 - 7. Within this range, plants will absorb and process available nutrients most efficiently. If the pH is too low (acidic), salts bind nutrients chemically, and the roots are unable to absorb them and the plants won’t feed. On the flip side, an alkaline soil with a high pH causes nutrients to become unavailable. Toxic salt build up that limits water intake by roots also becomes a problem; get to know your water.
Hydroponic solutions perform best in a pH range a little lower than for soil. The ideal pH range for hydroponics is from 5.8 - 6.8, slightly acidic. A bi weekly test should be part of the maintenance process; adding products to pH up (potassium hydroxide and potassium carbonate) and pH down (Phosphoric acid) add cost to maintain the hydroponic living walls.
The amount of dissolved oxygen in a nutrient solution depends on the water temperature. Cold water can 'hold' more dissolved oxygen. A fully aerated solution at 20°C/68°F is 9 - 10ppm; at 30°C/86°F it's 7ppm. According to Dr. Lynette Morgan, Director of Research at SUNTEC International Hydroponic Consultants based in Manawatu, New Zealand, root oxygen requirements double for each 10°C rise in root system temperature (max 30°C/86°F).
The dilemma for the maintenance technician is that with a 10°C rise in temperature, root system oxygen requirements will double, while the oxygen carrying capacity of the solution will drop by over 25%! The nutrient dissolved oxygen is unable to supply the roots’ oxygen demands, leading to prolonged oxygen starvation. Oxygen starvation will result in slow growth, mineral deficiencies and root die-back. Oxygen starvation will stress the plant, leading to an eventual attack by opportunistic pathogens, such as ever-present pythium aka root rot. What Dr. Morgan is describing is the anaerobic environment that is the naturally occurring environment of hydroponic systems.
DIY Equipment & Set Up
For the most part the equipment needs are pretty simple. Assuming we are talking specifically about hydroponic green walls – I’m not going to talk about ebb and flow nor aeroponics - specifically we are utilizing a top feed configuration; water solution is pumped up and allowed to drip through the media back to a reservoir. Pending the size of your wall, freestanding or wall mounted, you need a reservoir, pump, inorganic media (what will physically hold the plants), test kits and sterile tools.
For a reservoir the basic of plastic containers will work fine depending on the size of your wall. Some more advanced applications also contribute to the cosmetics of the system; stainless steel and decorative pools are not uncommon but because of the sensitivity of the solution, the exposed reservoir is subject to becoming a catch all for garbage or debris immediately altering the dynamics of the pH.
As a word of caution, take careful consideration of your reservoir as it is the life line to the success of the wall. For larger walls and walls exposed to evaporation, a fill float can be retro fitted to the reservoir. The color of your reservoir will also play a part in the water temperatures. As we discussed earlier, higher water temps result in less oxygen!
There are also a variety of pumps available; my experience as a pond builder would lead me to the magnetic drive types that seem to last more over continuous use. When choosing a pump the key is to understand how much water you need to pump at what rate and the height you have to pump it. The key here is what we call the “Head Height” or maximum height the pump can push water. Head is measured in length and the pump capability of flow vs. height.
For example, the height from the top of the reservoir to the top of the wall is 10 feet. Searching the internet we find literally thousands of options. A statistical rule is to double the psi (pound per square inch) to determine the head in which the pump will pump zero gph (gallons per hour).
Table 1 shows the actual “Head Height” taking into account the reservoir is not part of the calculation. When configuring the actual pressure needed to reach the maximum height, the equal distribution of water going through the pump through the supply tube while it is in the water is equal to the water weight outside the tube until it exits the reservoir when gravity and the actual weight of the water in the tube come into play.
Table 2 is a common and easy means in which you can determine what the minimal needs would be to reach the height needed to irrigate your wall.
The life line of the system can be viewed as if it were a human. The pump is the heart, the tubes are veins and arteries, and the solution is the blood carrying nutrients to the remainder of the body - all must be in working order.
Constructing Your Hydroponic Living Wall
For the most part the steps are simple. Start with deciding on an area with good light and recirculation air flow. I have seen various types of armatures that are tapered from the top of the wall down to the bottom so we end up with about six inches from the bottom of the wall.
Figure 1. In most cases the walls are flat at a true 90 degrees. This tapered angle, however, will prevent the irrigation water from dripping off the leaves allowing it to follow the angle of the rooting media.
The following sequences of pictures are from Peter Kastan and provide a real hydroponic wall installation:
Step 1: Armature and Mounting Framework
Step 2: Mounting the PVC Sheets
(Purchase at Home Depot or similar store) 15 – 3 f2 sections @ $39.96.
Step 3: Mounting the Rooting Media
(Geo – textile, open cell foam, coco husk, Doodlebug Rolls, etc.)
Rooting Media Complete, with Partial Plant Installation:
You can visit Peter at http://junglewallsmiami.com.
Going the Single Source Manufacturer Route
It may seem I'm pointing out a lot that go wrong with a hydroponic living wall system, but that is the point when dealing with a DIY project in particular. Of course, you have the option of choosing a patented hydroponic living wall system if you don't choose the DIY route. The greatest issue to consider here is scale and cost - of the system itself, installation, and maintenance plan.
While most of us probably can't afford Patrick Blanc and his Le Mur Végétal (Vertical Garden) living wall system, there are other proprietary hydroponic systems to consider - here a few:
There is a lot more to hydroponics than a simple pump and solution to feed the plants. And, living walls are not for the faint of heart when it comes to experimenting with someone else’s investment. When going DIY, my advice is to try various materials that are locally available, get advice from your local hydroponic supplier and set up your own trials and research.
I have pointed out some of the variables that will determine your project a success or a maintenance catastrophe. There is much more to the hydroponic living walls, including the highly variable topic of plant material – both inside and out – and I have only scratched the surface of the many highly advanced systems and applications.
George Irwin, The Green Wall Editor
Deception, Death of a Green Wall…
By George Irwin, The Green
September 2, 2011
me premise this post as a reality check for living walls.
No pictures, no examples, just my opinion. Over the years
of my experiences of trials, I’m seeing living wall failures
masked with pictures and unreal expectations. Like the
stock market, it is time for an adjustment to bring this
industry back to a beneficial level of reality.
It has been over
three years since my
first post about Green Walls (March 2008). Since then
we have seen a rise in popularity for green walls being used in
advertising, cosmetics, and urban agriculture, with claims for
green walls acting as additional insulation, adding 30 points to
LEED credits, and even cutting electricity by 20%. In
short, some of the pictures and the statements advertised are
bordering on blatant fabrication.
In the 1990’s and
2000's it was Patrick Blanc's innovative hydroponic system
leading the way and hoarding the attention for his lush,
bountiful displays. Through his example, many, including
myself, saw the potential of this industry. Today there
are more than enough newcomers, some blatantly knocking off
patented technologies; I can’t keep up with the system designs
and claims. Plastic boxes with bags, wire mesh with jute
fabric, racks that hold potted plants, Do It Yourself felt
fabrics, most of these are deemed “One Time Use” with the
development of such products destined to becoming a novelty with
no proven longevity or use beyond a single outdoor growing
season, not to mention becoming a potential safety hazard if
hanging more than six feet off the ground.
Personally, I have
read recent blogs and articles painting living walls in a
negative light questioning the viability and longevity of green
walls. Fair enough, you don’t see websites that highlight
the failures. To my own testament, I, too, have had a wall
removed because of the lack of experience from a maintenance
Since 2007 I can
attest to my own development and data collection that has lead
to our improved maintenance techniques, dramatically improving
survivability. However, I have never seen a reduction of
electricity by 20%, and a recent article explains how some
systems actually cause a greater carbon footprint than they
purport to reduce. Is it green wall deception?
are many products available to the consumer, contractors, and
various installers yet, in my opinion, a large majority of
these lack the training and education to maintain the green
walls after the installation. Let’s face it - the ability
to use a level, cordless drill and a little physical exertion
doesn’t make you a green wall expert. It is not only the
system's design that's important, but the long term science and
know-how that provides success: it’s the service after the sale.
And the greatest
learning experience is a failure. Failure has been,
frankly, my own motivation for improvement. The issue in
the industry, and specifically with a few of the systems, is the
fact they do the same thing, time and time again expecting
I have seen
everything from green roof media to top soil being used as a
growing medium for living walls. Some now use a coir husk
that simply acts as a holding mechanism for a root structure,
while the chemical bath keeps the plants alive, or at least that
is the way it’s supposed to work. The structural advances
of living walls are far and few. As mentioned earlier,
racks to hold potted plants, boxes with bags and felt pockets
are nothing but a means to hold plant material.
The real advances
are now in the growing medium and improving holding structures
that promote healthy plants. The science behind the system
is what will prove viable, long term success. Getting back
to my earlier point, just because you can use a level and
cordless drill does not make you a green wall expert. The
true success is being able to sustain the walls in a manner that
will prevent plant replacement year after year, or in some cases
on a weekly basis.
The amount of
knowledge needed for success in this arena is overwhelming.
You have to be an expert in design, irrigation, indoor and
outdoor plants, growth media, lighting, pest and disease
management and fertilizers; this doesn’t sound like your average
contractor. To compile the problem, there are more than
enough bloggers, architects, designers and members of the
industry who seem to have all the answers. There is more
than enough information, some good and some not so good, in
cyberspace to confuse anyone, if not everyone.
I believe living
wall success will rely on the combination of skills from an
individual or company that offers services from concept,
installation and maintenance to long term warranties.
Recently I heard of a wall being installed at a high profile
college outside of Philadelphia where the owner was told, and
accepted the fact that, “All the plants are going to die and
will have to be replaced after the first year anyway.”
This was astounding to me that such an assumption was even
The reality of
living walls is the long term education and training that is
associated with the ability to apply multiple disciplines.
I’m going to quote myself, “If you have a potted plant and you
place it in the dark closet, you don’t water or feed it and the
plant dies, do you blame the pot?”
The same is true
with living walls, you have to accept and understand that living
walls require an extended know-how that cannot be provided by
every landscaper, contractor and architect. The most
frustrating situations for me have included the project owners
who insist they can maintain the walls. This does nothing
to help solve the failure rate and it puts living walls in a bad
light when one does fail. These systems are not
maintenance free. Providing a plant the needs to survive
on a wall, at times over 10 stories high, is not a feat for the
inexperienced, yet some consumers are fixated with the allure of
living walls with little to no understanding for long term
maintenance and survivability - and for that fact neither do
some of the existing manufacturers. Designing and creating
a holding structure is a far cry from being able to sustain the
long term health of a living wall.
complicating issue involves the hype of the real benefits of
living walls. Fact is I have personally yet to see any
long term data that can prove anything concrete other than
aesthetic improvements. I have posted our own data about
the findings of our field studies, however, I have yet to see
any formal long term data on energy savings.
One website claims
that the living wall will protect the façade. Here is one
piece of reality: rhetorically speaking, can I justify a living
wall at the cost compared to the exterior façade replacement?
Green walls will protect the façade, however, the façade is
designed for the exterior use anyway, so by protecting it where
is the real return on the investment? Where is the
façade and façade penetrations don’t protect a whole lot of
anything, in fact you have now damaged the façade via the
penetrations. Also, if the manufacturing system
representative you chose is not knowledgeable about plant
material, did you account for the potential plant replacement?
And show me a living wall that can provide 20% savings on
electricity, I would love to see it.
But not all is
negative! I do agree the walls provide a wow factor and
benefit employee production, improved air quality, improved
acoustics and can be a viable use for urban agriculture, but
that’s only if they don’t fail, require high numbers of plant
replacements, or just outright become a burden.
Are all green walls
to be classified as sustainable? No way, not in my book.
For one, some of the materials used to manufacture the units are
in question. For example, one common material is plastic
which in itself is not a sustainable material. In fact,
LEED prefers the use of metal over plastic, making the LEED
points applied to plastic systems contradictory.
Never thought I
would be the one to write such a post but I’m a realist.
The point of this post is not to give living walls a bad rap; in
fact, the intention is to bring to light the reality of what can
go wrong and how little the industry and many installers truly
as an educator and an authority on these technologies is to
protect and inform. The best use of failure is to learn
from it and not repeat our mistakes. I'm sure others are
not selling walls hoping they fail, but many people forgo needed
changes just for the sake of another sale.
Although others are
planned, currently there are only a few university green wall
system and benefits testing going on in North America -
BCIT and Maryland - and these studies will eventually help
the industry and hopefully prevent dreaded deaths of green
walls. Yet for now, consumers beware.
architects and consumers, my advice is to move forward with
living walls under the pretense that not all are created equal
and each system has its own application. Hydroponic vs.
media-based are only two technologies. Educate yourself
and gain an understanding of the science behind each system.
Know you must be invested in your purchase in order to increase
the likelihood of survival.
I have seen some
beautiful successful walls, both interior and exterior.
The success of such walls are the result of a well rounded
research, design, training, installation, and maintenance
program. Utilizing the right plants in the right setting
for the right system as well as understanding the science behind
the technology are key to your green wall's longevity.
George Irwin, The Green Wall Editor
George Irwin is the President and CEO of Green Living™ Technologies, LLC (GLT) based in NY. Green Living™ Technologies is the only U.S. manufacturer of growing media based green wall and three types of green roof systems. Mr. Irwin is a former trainer for Green Roofs for Healthy Cities Green Walls 101.
Contact George Irwin at: GreenWallEditor@greenroofs.com, George@AGreenroof.com, www.agreenroof.com, or 1.800.631.8001.
The Next Add-On Service for Green Roofs and Green Walls
By George Irwin, The Green
May 24, 2011
Photos Courtesy of George Irwin, unless otherwise noted.
Last time I told you how I was long overdue for a new column post but was torn between two topics of interest, remember? Well, after Green Walls and Winter Interest, here's the second one - my take on the latest profitable service for landscape contractors, roof garden and green wall professionals and garden lovers alike.
The agriculture industry has evolved to create one of the most diverse and competitive industries for contractors, architects, landscape architects and designers. The economic downward spiral over the years has placed more pressure on companies to sharpen budgets and to offer additional diverse, one of a kind type products and services. As a business, you have to truly think about the services you offer that will make you stand out, focus on the ones that are profitable, create acceptable profit margins, and attract clients that warrant a professional.
If you recall the boom in pond installations starting in the 90's, everyone wanted this exclusive water feature and, of course, at one time only a handful of companies offered such a “specialty” service. Yet eventually, after someone does something so successful and spectacular it tends to evolve into something more mainstream. These specialty services are also often new to a company, and success rates, knowhow, and the unknown can be initial hurdles.
After some needed training and experience, we know the modern development of green roofs and vertical walls provided add-on opportunities for landscape/construction, design/build, design, product manufacturing, nursery growers, irrigation and long term residual maintenance professionals.
Tomato & basil on an A-frame.
So what is the next great service, you ask?
Small scale backyard farms of edible landscapes are the new “pond building” boom, and edible walls and roofs are the new landscape.
Although we are not seeing the green roof residential market competing with the commercial, education or government sector in terms of economic scale, there is a continuous growing trend towards residential and small commercial scale urban farms.
Currently, there are a handful of companies in the U.S. who have added edible landscapes as part of the service package they provide. On a larger scale, commercial urban farms are far and few but gaining popularity. And these urban farms can include everything from design services, installation, and maintenance to harvesting.
Urban farms are an amazing add-on feature for the green roof and wall market with great potential, and now commercially available vertical agriculture beyond conceptual stages are taking the industry to higher than average profits, showing a return on the investment of around one to two years.
Peppers & greens together in a green wall.
Each year after operating expenses, returns on the initial capital investment can be 50% - 75% of the initial investment. Unlike ponds or water gardens, food is not an option and the public awareness and desire to have high quality, fresh produce close to home is a market virtually untapped with an unprecedented promise of success.
Opportunities now exist for the new corner store to become the state-of-the-art vertical farm backed by organic and food safety certifications that can grow everything from tomatoes, greens and specialty crops year round, indoors, in almost any building.
From small scale residential raised beds to simple but sophisticated larger vertical farms, fresh produce has evolved as the next service for the landscape industry. And, the burgeoning trend in rooftop agriculture is providing an as yet untapped boom for the green roof industry.
Rooftop farms are beginning to bring some fame, and if not yet fortune, certainly lots of media attention due to the newness factor.
See the not-so-small 40,000 sf Eagle Street Rooftop Farm below:
In recent years there has been a clear increase of public awareness and educational programs around urban farming and produce, from professional organizations like Green Roofs for Healthy Cities to non-profit organizations such as Urban Farming to private companies like many of our own collaborations here at Green Living Technologies. The consumer market is reaching out and craving for these products - restaurants, school lunch programs, classroom education, etc., and I believe the public “urban-you pick-it” is the next franchise model.
Different kinds of lettuce in one green wall module.
Recently, I had the chance to host a training at one of the largest hydroponic tomato growers in the U.S. northeast at an incredible 12-acre facility heated with methane gas costing very little to heat after the initial investment. The potential for large scale food production is great, yet we recognize the need to diversify hydroponic technologies to include new and improved techniques. By advancing this successful model with incorporating additional vertical technologies, we’ll have the capability to produce crops beyond just tomatoes.
Rows and rows of hydroponically grown tomatoes.
Although this large scale commercial facility services large clients such as grocery stores, it is the smaller, more personal one-on-one customer relationships that will provide the greatest potential for truly local produce, plus possibly provide the highest margins for the edible landscape. Of course, both the large and small scale urban ag growing facilities have their place in the market for food production, but the point is we need to diversify our crops to reap the greatest rewards.
For hundreds and thousands of years, people, communities, and cultures have always come together over food and a meal. Not only would these future urban ag centers provide healthy local food but they could also be the catalyst for bringing communities back together, wouldn't you agree?
George Irwin, The Green Wall Editor
Green Walls and Winter Interest
By George Irwin, The Green
Photos Courtesy of G-Space Design, Project Manager and Certified Product Installer
March 18, 2011
Green Walls can’t survive in the cold; they don’t look good in the winter; they are only viable in the south or indoors…..Think again! There is more science behind a green wall than you may think.
I am long overdue for an updated article but was torn between two topics of interest. I was set on talking about the latest profitable service for landscape contractors and garden lovers alike when the timing couldn’t be better talk about these green wall images I recently saw in a newsletter. The winter interest is just as dynamic and provides incredible pallets of delightful colors.
What happens in the winter? Read on my friends and lovers of vertical bliss. It’s time to put an end to the banter about green walls and winter. Not only can they survive, they can be gorgeous! I was reading the newsletter from Michael and Angela Bucci, owners of Philadelphia based G-Space Design and Philly Green Wall & Roof where they featured multiple walls that display just as much interest in the winter as they did in the spring and summer.
The wall below is one of many at this particular location in the Philadelphia area. I enjoyed this wall the best, with the enhanced purple and red ground cover providing an accent to the blue in the wall. The transitioning from late fall to winter is undeniably just as interesting as the blue becomes brighter and the purple gets more intense, all while retaining a green surround.
Philadelphia, PA Green Wall
Left, October 3, 2010; Right: January 6, 2011.
The success of the wall is all about knowing how the plants react in their geographic region and elevation. Specifically, the Mondo Grass keeps a green color, tips have browned; Hosta Francine is completely dormant, all leaves have browned; Blue Star Juniper turns a bright slate blue color; Lysimachia aurea has some brown and drooping leaves; Huechera Purple Palace displays bright purple, Purple Phlox has some green retained and the Sedum ternatum shows bright green color all winter.
Without disclosing all the science behind the success, I will tell you that much of what we see here is due to preventative maintenance. This is not to say there have not been extensive trials and, in fact, mistakes. Some plants simply don’t provide winter interest, like the hosta or other perennials.
Below is the noted PNC Bank, still the largest exterior wall in North America and by far one of the showiest as the color variations provide both texture and contrasting variations as the seasons change.
||Ajuga 'Black Scallop'|
Huechera 'Purple Palace'
Left: September 2010; Right: 2nd winter February 23, 2011.
When we teach maintenance, it’s not so much the amount of pruning and time on a lift or ladder (I wrote about maintenance in October of 2008). Besides having access to the wall, following a standard irrigation checklist and keeping the catch basin clean, the preparation for the winter is one of the most important maintenance visits throughout the year.
Unlike plants in the ground which are protected by snow, mulch, and other wind deterrents, green walls are subject to harsh conditions yet the plants are unlike traditional sedum for green roofs and are susceptible to the enhanced and harsh conditions of winter. Much of the decorative walls are not sedums and can be very delicate, making them susceptible to the harsh winds. Wind tears at leaves and removes moisture from both the plant and the growing media. The key is to prevent the plant from losing moisture during the winter months.
We protect the green wall from moisture loss two ways. The first is a trade secret, but the second I’ll gladly disclose and say that periods of warming provides an ideal time to irrigate the walls in the winter.
YES….the irrigation should be turned on when there are breaks of warming from 35 degrees or higher. Microscopically, the roots are seeking water during these times and without it the plant will die.
Philadelphia Gateway Project: Summer of 2010
Dwarf Mondo Grass - mostly brown, some green at base of leaves
Sedum rupestre 'Angelina' - reddish orange color
Sedum 'Blue Spruce'
Sedum album 'Red Ice' - reddish color
Philadelphia Gateway Project: February 8, 2011
It has been a thrill to be part of an industry where there is a handful of successful science based green projects. On the other side, it is the new opportunities to create jobs and provide the next new paradigm shift in technology that is exciting.
Planting a wall and hanging it are only the beginning. There is science behind success. The failures could be linked to many variables including product, growing medias, plant choices, irrigation and much more.
I feel there needed to be some clarity on the subject that not all green walls - and the experience behind them - are linked to the industry as a whole. Not all green walls can survive the winter, however, many can while providing much needed winter interest from the living, breathing, plants.
George Irwin, The Green Wall Editor
The Original Green
Basis for Great Design
By George Irwin, The Green
Photos Courtesy George Irwin Unless Otherwise Noted
September 26, 2010
Mother Nature: A great designer!
something is successful it’s only natural to emulate that same
success. Green wall technologies are no different.
As the owner of three patents, I find myself grinning in
disbelief that someone would think so highly of what I have
invented to copy it as their own.
Laws today prevent intellectual property from being duplicated,
however, Mother Nature cannot be patented. No one company
or person has claim to inventing the Living Wall except for hers
truly, Mother Nature. Since the days of time, plants have
been growing vertically! I want to take a step back and
look at the science and beauty of natural green walls and how
the principles are applied to some of the technologies available
The vitality and survival skills of plants are remarkable,
provided an opportunity they can adapt to the climate and
location. Through the process of phototropism, growing to
the light source, plants increase vitality and survival rates.
Below are clear pictures of celery and broccoli growing out from
an edible wall to the light source literally growing out of the
wall and turning up at a 90 degree angle. This has been true
with other vegetables and green wall plants. (For sake of
argument we are specifically talking about “Living
Walls” only.) Even when bearing heavy fruit, the stems
of the plant reach for the light.
Celery & Broccoli – Reaching for the light from an
my lectures, I refer to living walls as a pot that can be
elevated to hang on walls (or freestanding) - it’s not that
simple but my point is, if you have a potted plant and you put
it in the closet and it dies do you blame the pot? Of
course not, plants like people, have needs. For the sake
of this article, I am not going to address the obvious elevation
and lighting needs. Not all plants (or living walls) are
created equal; the amount of sun and elevation requirements are
unique to each plant variety.
Ferns, mosses and more creating a natural
interwoven vertical tapestry of plants.
features behind successful living walls are those duplicated by
nature. The definition of Living Wall includes a root
system throughout the entire structure, either with or without
growing media. There are a variety of individual plants
throughout a wall, depending on the geographic region, each with
its own root system.
In my opinion, in order to create a successful wall, plants need
a structure or mechanical method to anchor and areas for the
roots to expand and “Grab.” In the natural living wall,
this can be seen as plant roots traverse through cracks and
1 below shows the extensive root system that stabilizes the
growing media and locks the plant into the system. Even
mosses microscopically grab the rough surfaces of the rock face.
Figure 1: Cutout of the
developing root system.
are more successes with commercial living wall systems that
allow for the “Grabbing” action of the roots. Larger
pockets or bagged areas won’t allow for the roots to grab, but
instead literally hang in a fabric mass of contained roots and
growing media. That’s not to say all the living wall
systems with structured cells are complete. In some cell
technology systems, the configurations do not allow for the
roots to migrate or at least enough to accommodate the fullest
needs of the plant. This incomplete configuration does not
provide areas for the roots to expand, and eventually creates a
series of root bound plants, something to consider when choosing
Figure 1 shows the natural development into the pockets between
the rock face and grabbing power as the crevices act as areas
for the roots to anchor. These crevices could represent
the cell structure of an artificial living wall system.
Left: Bagged type Living Wall showing signs of
pressure pushing the front wall forward.
(Red line shows the bend.)
Right: Close-up of the bag protruding through the
Stabilizing the plant is only one element to successful man made
walls. Duplicating irrigation and nutrition can be tricky
since stormwater is the source for natural green walls.
Because they are vertical, it is easy to see that water runs off
from the ground above and down along the walls bathing the plant
and roots. This water will contain the natural nitrogen
(N), phosphorous (P) and potassium (K) for each region, in
addition to the trace minerals that will naturally feed the
plants - does this sound familiar?
designed form of growing plants is the technique of
"aeroponics," the process of growing plants in an air or mist
environment without the use of soil or an aggregate medium,
bathing the entire plant while providing small and short does of
synthetic fertilizer. This method of growing was
originally developed by NASA to grow produce in space when the
astronauts were orbiting for extended missions.
Similar to aeroponics, the second technique of growing without a
form of media is hydroponics. According to Wikipedia,
plants may be grown with their roots in the mineral nutrient
solution only or in an inert medium, such as perlite, gravel,
mineral wool, or coconut husk. The techniques are both
reliant upon a chemical solution to provide plant growth.
French botanist Patrick Blanc created his hydroponic
Mur Végétal (Vertical Garden) living wall system
attempting to copy what Mother Nature has accomplished, at least
in the irrigation methods, with waterfalls as an inspiration for
his soil-less walls.
methodology was born from his time spent in tropical forests;
his design is simple in theory, duplicating the natural plant
baths of nutrient rich rain water. However, I believe the
ecological factor of some of the materials are in question,
specifically the waterproof sheathing, made of polyvinyl
is a wicking felt layer with pockets to hold plants; water is
recycled with a nutrient bath of synthetic fertilizers.
The design, not difficult to duplicate, is visually effective
and many times stunning, however highly mechanical. In
fact, if there were a mechanical failure or loss of power for
extended periods of time, it is likely the plants would dry out
and the wall would suffer a higher than normal plant
Figure 3: Close-up of the layers of Patrick Blanc's
hydroponic green wall: steel frame, PVC, felt,
means of hydroponic design was conceived to duplicate the
tropics, and in some climates the excessive water is open to a
myriad of complications. For example, hydroponic systems
should be highly aerated to provide oxygen at the root level;
the lack of oxygen and warm root temperatures are the leading
cause of plant loss. Also, non sterile reservoirs are
breeding grounds for water borne pathogens, such as "root rot,"
a generic name for Pythium, Verticillium, Phytophthora, and
Fusarium, opportunistic waterborne diseases that can seriously
affect indoor and outdoor plants.
There is another technique that combines bags, cells, and
hydroponic growing. The system contains bagged coco husk
allowing for the roots to grab into the media as the bath of
nutrients provides the life sustaining nutrition. The
benefit to such a system, if hydroponics is in fact the system
you choose, is that unlike other hydroponic growing, the coco
husk will provide a root area to grab onto and lock the plant in
place. The resource in question will always be the use of
water and synthetic chemicals.
Hydroponic vs. Media Based Living Walls?
From my perspective, the advantage of a media based living wall
lies in the fact that the media can support beneficial bacteria,
micro-organisms, and provide a matter to hold water. Some
of these types of walls can go a week with no irrigation, and
some indoor walls can go two weeks. These micro-organisms
need food to ensure they will grow and multiply, however, any
harmful organisms will also feed and grow. This is why it
is important for free drainage and the ability for oxygenation.
Harmful pathogens tend to thrive in anaerobic conditions,
whereas beneficial organisms thrive in aerobic conditions.
Here is one of my secrets: Mycorrhizae. Mycorrhiza is
specialized fungi that colonize plant roots and extend far into
the soil, and is a beneficial fungus that prevents pathogenic
fungi from growing on the roots. If you are growing in
soil, in our case the GLT bioSoil designed specifically for our
living wall media, including mycorrhizae is ideal - especially
if you are feeding the plants an organic food. In our
case, we use a 10% blend of our bioSoil with mycorrhizae along
with other matter that is proprietary. Mycorrhizae thrives with
an organic food source. Synthetic fertilizers destroy the
mycorrhizae which is why they cannot be included as part of the
hydroponic system, leaving the technology open to common root
Vertical wall technology is pretty simple. You have to
provide a means for the roots to grab and lock themselves in,
free drainage to prevent sitting water, proper means for root
development, and choose the correct plant for the geographic
region and elevation.
Nature's original green wall prototype with water
running off the wall into a stream below.
Duplicating Mother Nature is no easy task - duplication and
success are feats only few green wall companies can stake claim,
and some better than others. As a consumer, choose wisely
beyond just a product price point. The actual product -
its function of replicating nature and its longevity, should be
the basis of your search. Green wall knowledge and plant
science, service, reputation, and obtaining references are the
best ways to determine what systems are right for you.
short, find the longest lasting product from a manufacturer you
can trust to weather the elements and a source who can provide
the science and service to back up Mother Nature's original
George Irwin, The Green Wall Editor
and Growing Media:
Change is Good
By George Irwin, The Green
Photos Courtesy George Irwin Unless Otherwise Noted
April 21, 2010
the usual spring article when I'm usually complaining about being
busy with tradeshows and with preparation for projects or travel,
here it is April and I did not get my first article ready by February
as anticipated. I’m much disciplined when it comes to getting things
done on time, so I'll blame it on others around me for being so
and clients are just as busy. Why is everyone so busy? I’m blaming
technology. Before computers, PDA’s, cell phones, mobile Web and
laptops, it actually took days to send a letter - now a million
be sent in a single click, and the need for instant gratification
sometimes supersedes quality.
in technology has brought about change and, in most cases, change
is good. Products become better suited and applied, projects
become bigger and more intricate. The same is true for green
In January I had a chance to be a guest speaker at the
Tropical Plant Industry Exhibition (TPIE) in Fort Lauderdale,
Florida. One of the great things about being a speaker is
you have an opportunity to walk the tradeshow floor, meet others
who are doing research, propagate new ideas, form new relationships,
and see new developing products.
to be shaping up as what I see as the “Minimal Use Vertical Wall”
with a handful of new green wall companies. Nothing bad about having
a new company, we all started somewhere, however, not all green
walls are created equal. In fact, I have always talked about
the advantages of products developed for long term use. Let's
face it, there are some materials we don't want, or trust, hanging
on walls four stories high, but if you want to dress up your back
yard fence with a lightweight option (re-planting them year after
year), these minimal use green walls may be your answer. For example,
there are plastic bags and canvas pockets that hang from a wall,
another one that looks like a baby diaper pinned together, and the
ubiquitous upside down tomato growing sock.
green walls become more popular, the projects become more intense,
the spectacles become more dramatic - and so can the liabilities.
As an industry spokesperson and a frequent visitor to industry shows
and events, two of many key questions I always seem to get asked
include the liability of installing green walls, and type of growing
media for green walls.
that broken plastic is securing the product to the bracket.
talk about liability; here is where we may run into problems with
new, unproven companies entering the green wall market. Some
of the products offered are for all intents and purposes, bordering
on novelty or single season use (use it for one summer and throw
it away). For example, some of the products I have recently
seen or experimented with are advertising and displaying higher
mounting elevations than I would feel comfortable with installing.
very few commercial grade green wall products with a proven track
record that are made to last indefinitely, constructed from materials
to meet wind and weight loads, accommodate extreme variances in
temperature and to withstand other regional abnormalities (e.g.
salt tolerance around coastal regions). Some of these new
green wall products, specifically some of the living walls, have
no track record at all.
I encountered a press release from a “New & Exciting” company introducing
green walls. After some in depth investigating and direct
knowledge, the company had no track record of manufacturing, installation,
training, certification, or a portfolio behind them.
qualified to install green walls? According to the
Chicago Tribune article "Turf wars, Chicago-style: Roofers vs.
green-roof landscapers" of October 2009, the
National Labor Relations Board (NLRB) favored the landscapers
over the roofers to be capable of installing green roofs at a lower
cost, and referring to roofers they pointed out that "they are no
less experienced but are more efficient at installing green roofs.”
Green roofs, fine, there is more than enough training opportunities
to learn about green roof installations; some companies provide
a professional certification course that credits them to be "Certified
Professional Installers" for that company's products, and other
opportunities are more generalized such as the Green Roof Professional
(GRP) accreditation offered by
Green Roofs for Healthy Cities.
and I accept the verdict by the NLRB hands down. I do, however,
have to speak openly about landscapers installing green walls.
Some of these projects, not all, involve a level of construction
not normally associated with traditional ground elevation landscape
work. I can freely comment because I was a landscape contractor
for 23 years before I, too, entered the green roof and wall arena
In comparison to traditional built in place green roofs, for the
most part a green roof tray system is relatively simple to install
- once on the roof it’s a simple matter of safely getting the trays
in position, and adding irrigation - which should be part of the
landscapers' knowhow. Overall, most roofers do not have the
background or knowledge set to diagnose and treat problems relating
to plant health, whereas the landscape contractor is ideal to be
the stand alone green roof installer and maintain the vegetation.
1. Proper scaffolding is a serious job.
say all green roofs are that simple, but for this purpose it’s just
not the same as green walls. There are no standards for green wall
technology, with multiple systems to choose from including green
façades and living walls (both growing media based and hydroponic).
Each system is different and each manufacturer should provide some
type of formal, recognized training for a safe installation and
the long term safety of an often large product hanging from a
skills associated with the assembly of such systems require extreme
measures necessitating specific training; it’s not about simply
screwing brackets to a wall. For example, one of my company's
projects, the PNC Bank project in Pittsburgh, PA, left and below
(Figures 1 and 2), was prepared by
G-Space/ Philly Green Wall and Roof, a skilled, state licensed
design/build firm certified under our product's brand, and not installed
by landscapers. The vegetation was already mature and grown
into the system by a horticulturist and/or a growing facility, and
thus did not need the additional plant expertise of an experienced
landscape contractor. In this case it wasn't about the welfare
of the plants, but the physical installation including engineering,
crane operations, calculations, mounting hardware, job site preparation,
scaffold safety, fall restraints, etc.
2. Prep Work to Accept a Living Wall.
type of man lift.
not to say this is the norm for all green wall installations.
In my personal experience, even the largest of landscape firms we
have worked with globally do not have the knowhow, experience, and
insurance coverage to conduct a large scale green wall installation
over 20 feet high. Yet, it is here I have to cross over the
line and lean to the landscapers to rely upon for continuing maintenance
procedures. Pending the scope of work construction, contractors
are the large scale installation experts, and the landscapers and
growers are the plant experts who should, by all rights, also be
the maintenance personal.
the question about additional liabilities and working with extended
heights. May I remind you that the landscaper is not traditionally
adapted to working on scaffolds or in a man lift (a machine that
is like a boom that carries a person to an elevated height).
Green walls provide a new paradigm to the responsibility and job
description of the landscape contractor. This puts an even
bigger burden on the manufacturers to ensure they provide resources
for the maintenance technicians, requiring additional job safety
training and new equipment training. There is a place for both the
installing contractor and landscape contractor; having a company
who can provide a single service is ideal. Experience is a
foundation to lean on as a consumer, and “New & Exciting” could
potentially equate to “Dangerous & Liable.”
The second question that is always asked when I’m speaking or in
conversation is, “What about the growing media?” I always
respond, What about it? Fact is, for every company there is
more than likely a different method or medium they
grow in. I always use the word green wall loosely and remind
people that "green wall" is an all-encompassing term. And
growing "media" is the plural of growing "medium," so unless you
have more than one type of growing mix within a project, it should
be referred to as growing "medium." And when we're talking
about growing media, there are two areas to distinguish between
regarding placement in a green wall.
Living Wall - Saul Nursery, Alpharetta, GA, Photo by
Right: Green façade - Desert Ridge Marketplace, Phoenix,
defining a green wall as a green façade, the growing medium would
be found at the base of a 3-D trellis type structure to support
climbing plant material and vines. In this case you should
have a growing medium that is rich in nutrients, drains well, and
has a pH level to support the type of plant material in its particular
The Musée du quay Branly
Hydroponic Living Wall by Patrick Blanc.
defining a green wall as a living wall, that's a completely different
story since there are multiple locations to place the growing media
- or none at all. Follow up questions are necessary!
So when someone asks me about the growing media used in green walls,
first of all I have to politely ask if they're actually referring
to a "living wall." In confusion, the general public simply
assumes because it's vertical, it's a living wall. (You can
archive of one of my earlier posts that clearly defines the
differences between a green façade and a living wall.) I've
found that more often than not, the question is clearly directed
towards a living wall.
matters worse, the ever popular work of French botanist and designer
Patrick Blanc is defined as a true hydroponic living wall.
This means it does not contain any organic growing media; the plant
roots are fed with circulating water containing nutrients.
The definition of a living wall states that the roots are evident
throughout the entire wall, not just at the bottom as found in a
green façade. So, in this case, we have two types of living
walls - one with a growing medium and one without. Back to
the question, What kind of growing media is used in living walls?
Before I answer the question, you have to understand plants require
very few things, and aside from sunlight and the availability of
water, free drainage is key - the growing medium has to provide
the matrix to allow for water to flow freely in order to prevent
root rot, promote oxygen uptake and microbial action. Plants
also need to have the ability to extend their root system - if you
have ever purchased a plant where the roots are wound around the
inside of a pot, you know that plant is root bound and would have
eventually choked itself to death. A hard clay type of soil
would also restrict root development due to compaction and could
eventually kill a plant by drowning it.
Moss Wrapped in Wire Mesh.
to preparing the medium for plant roots, consider the plant requirements
in relation to light, water and nutritional needs. Other than
the lighting, which allows for the plant to produce sugars for energy
and growth, everything about your plant should evolve around the
roots. Using the correct composition of growing medium will
strike a balance of air space, water and nutrients - if you have
healthy roots you will have a healthy plant, and if you have healthy
plants, you'll have a successful living wall.
the new designs starting to emerge consist of a variety of wire
meshes shaped into forms that contain a 3-D block of sphagnum moss,
coir husk or rock wool. Other bagged type systems use or have
used anything from peat moss to potting soil to any of the above.
The hanging pocket types, or what I referred to earlier as minimal
use, suggest employing “a high quality potting soil.” So with
three different types of systems, you may have three types of growing
media and methods to establish the wall. And not all growing
media are equal.
Currently, there are a variety of mechanical means to hold plants
on a wall, but I feel the greatest advances in green wall technology
are going to be in the growth media field. Rock wool, coco
husk, and sphagnum mosses are all very porous and popular in the
allow for drainage, root growth and are lightweight. Cons:
They need a constant supply of irrigation and fertilizers, artificial
environment regulation (the need to always monitor the pH levels),
and there is no beneficial microbial activity, especially around
the roots of the plants.
View of a Coco Husk Insert.
other hand, quality potting soil mainly consists of peat moss; although
controversial and questioned as being a sustainable harvesting practice
since it involves older bog ecosystems, it provides the support
matrix needed to sustain plant growth. Media-based living
walls were introduced around 2004, and the growing media used was
a high quality potting mix. Personally, peat was the base
to one of our older medium recipes, with other added ingredients
and micro-organisms, which I can’t disclose because of trade secrets.
So I know firsthand that the type and quality of peat is of the
utmost importance. A newer bog provides a more fibrous peat,
which is ideal, allowing the final product to gather naturally to
form something like the commercially available pre-casted peat pots.
The fiber content in the higher quality media should be above 60%,
have a high water retention rate, drain freely, and provide a balanced
But the potting mix media also needed applications of periodic fertilizer.
To add additional controversy almost ignored and rarely published,
by comparison traditional lightweight extensive green roof media
hold minimal nutrients because of the lack of organic material -
and the result is the application of synthetic fertilizers to feed
the plants. Even though low maintenance, most succulents and traditional
sedum still need nitrogen (N), potassium (P), and phosphorous (K),
in addition to micro nutrients as part of a fertilizing plan.
When chemicals are not being absorbed, they become part of the runoff
in the traditional sense - the fertilizers are now making their
way to the waterproofing layers of green roofs and washing into
the combined sewers, drainage ditches and into our waterways, no
different from fertilizing your lawn. The same is true for the living
walls, no matter which growing media is present, fertilizer is going
to have to be added and will eventually contribute to runoff.
Recently I became aware of a medium designed from a fermentation
process using old shipping containers that is providing high quality
fibrous compost with a consistent organic nitrogen content of 3%
using chicken manure as the key ingredient. (Chicken manure
has been documented to leach into the water table causing harmful
effects because of the concentration when not removed or used as
a by-product.) The end product results in a concentrated N,
P, and K mix enhanced with additional micronutrient rich media,
while the process removes 100% of the methane off-gasses.
process in old shipping containers.
creates a compost and bio-fertilizer being used as part of the new
living wall growing media. These properties provide a benefit
for the green wall and roof market because it will eliminate the
use of synthetic fertilizers and it will not leach like the synthetics.
There is no runoff so it becomes the organic base to the advanced
living wall and roof media, and can be used as a top dressing to
all green roofs to replenish the nutrient values. For green
walls, a tea comprised of the fermentation is introduced to the
irrigation providing some of the highest quality of living
wall media available.
So, what is my answer to the ever popular question, “What about
the growing media?” Now you can see why I answer, “What about
Green walls are advancing; the means in which we secure plants to
the wall are numerous. The novelty is over and living wall
projects are taking on awe inspiring displays of art, function and
controversy. And questions of liability, construction, and
maintenance are still part of the unknown equation. I know
that the skills of many trades are needed and the skill set
needed cannot be seen as a standalone trade.
I believe change is good and advanced technologies will continue
to grow, and liability issues will decrease with increasing levels
of education and experience. I also believe that the next
wave of fertilizer-free growing media for both walls and roofs is
close to being commercialized. No matter what, the industry
has expediential room for growth and advancements, keeping us all
busy for quite a while.
George Irwin, The Green Wall Editor
Empowerment with Vertical
Agriculture, Edible Walls
Farming Food Chains
By George Irwin, The Green Wall
Photos Courtesy George Irwin Unless Otherwise Noted
December 15, 2009
Author's Herb Wall
you ever have an opportunity to talk with my family you'll see there are very few
things I am obsessed with except for my fascination with food.
Fortunately when I am home and not traveling, I have the means to
provide nutritious food such as fresh berries, raw vegetables and other
non processed edibles. I do 90% of the cooking; I make three meals
a day for my family - breakfast before school, homemade lunches, and
For me it is not just about making the food - I am obsessed with cooking
high quality nutritious meals that lack processed or frozen produce.
I’m talking specifically about not using frozen or canned vegetables and
eating ripe juicy fruit. I’ve been fortunate to be in the right
place at the right time but during these trying financial times not
everyone can afford fresh foods which provide the highest nutrition.
Fuel is at an
all time high, the U.S. economy is hovering above an economic crash,
houses are being foreclosed, unemployment is higher than ever and people
still go to bed hungry. Putting food on the table is one thing,
being able to afford a high quality nutritious meal is another.
Yet I also know too many families who don’t cook such meals simply
because it’s easier to stop at the local fast food store or to microwave
a frozen meal.
I was part of a
discussion group about Urban Agriculture the
in October, 2009, in Toronto as part of the
Cities Alive! World Green
Roof Infrastructure Congress. The theme was growing fresh produce in urban
environments, and there were some great projects implemented on roof
tops of inner cities, the use of abandon lots, and the concept of
Vertical farming is a breakthrough in socialized food production to help
feed the ever growing populations.
It was hard to think in a conceptual manner when we were already implementing
vertical farms as one of the most powerful applications of agriculture
ever. The concept of vertical farms is no longer conceptual!
are real, however, there are many concepts that still lend themselves to
including horizontal growing as part of the vertical concept, yet this
is not necessarily the case. It only makes sense for this column
to incorporate my love for food and my experience with
Vertical Agriculture since I have been involved with what is no doubt
one of the most incredible Vertical Farming projects to date; it’s
called the Urban Farming Food Chain.
Walls - Left: Diagram from GLT; Right: Patrick Blanc’s mur
végétal at Le Musée du Quai Branly;
Photo: Bill Bishop; Source: Human Flower Project.
Before I continue, let’s review the definition of “Living Wall” which
has a root system throughout the entire wall within its mechanism in
comparison to a “Green Façade,” better known as a 3D or wire trellis
type, where the roots are at the bottom of the structure and it is the
structure that supports the plants' climbing habits. Due to the
definitions, the walls of French botanist Patrick Blanc are defined as
Living Walls even though they do not have a growth media base and are
Author's Kids Planting
Back to my story - in 2005 we were preparing a test plot of plants with
our products for the growing season, I was home with both my son and
daughter who were 7 and 4 and wanted to plant something in the walls.
Here I was alone with two kids who wanted to literally play in the dirt,
something we as adults forget to do, that is “play.” My son found
some old lettuce seeds in the garage and this is what they wanted to
plant, but planting them in the ground was not good enough, they wanted
to plant them in our Green Wall Modules (which eventually became the
Green Living Wall Panels).
So we laid out
two Green Living™ Wall Panels, filled them with growth media and my kids
planted the seeds, painstakingly one at a time. If you know
anything about lettuce seeds they geminate pretty quickly. A few
days later my son discovered the germination and he made me hang them on
the wall. To my surprise, in less than a few weeks we had a full
panel of lettuce that we used for our own salads. This was the
start of a revolution; that same summer we planted tomatoes, cucumbers
and basil - we dubbed it the salad wall. The following year we
developed a 4 and 6 inch-depth green wall panel and were successful with
zucchini, leeks, strawberries, herbs and baby sugar watermelons.
We had no idea what we were about to realize - we can grow almost any
common crop literally in a vertical plane.
Our first Lettuce Wall
Two years later, I received a call from an architect, Robin Osler, whom
we have worked with in the past. To my excitement and curiosity,
Robin asked me if we ever grew food in our walls. Of course we had
just been through two years of authentic research/self use using our
Green Living Walls for growing food! Robin introduced us to Joyce
Lapinsky and Taja Sevele, the founders of an organization called Urban
mission is to eradicate hunger. This was perfect timing since as a
corporation we, too, were seeking a non-profit to adopt as part of our
corporate giving program. Social responsibility is a key value in
our business plan and Urban Farming’s mission was very much parallel to
what we believed in. Urban Farming, based in Detroit, has its
roots, no pun intended, in planting gardens throughout urban areas
utilizing vacant land to help feed the homeless. This land is not
always available, sometimes contaminated, and simply not always
accessible in urban environments. However, there is always
vertical space with walls.
Joyce, who is
the West Coast developer for Urban Farming, asked me about a Green
Living™ Wall growing food for the homeless in Los Angeles. From
here the Urban Farming Food Chain was born. Robin associated the
idea of a chain's having links and the links making up the chain with
each edible wall being a link in the chain that would connect the Edible
Walls around the world as part of the “Urban Farming Food Chain.”
Skid Row, Los Angeles,
Candice (Candice was a volunteer helping Joyce in Los Angeles) had spent
days and weeks looking for walls in the LA area, meeting with local
officials and building owners to grant the use of such walls.
Joyce found four locations to install the Edible Walls, I flew to Los
Angeles, and I had a chance to talk with the people we were trying to
help. Personally, I was in shock to experience the life of a
homeless person; I was at the epicenter of homelessness, the skid row
area, Gladys Park in the center of Los Angeles, 10 minutes away from
Hollywood and millions of dollars of revenues being generated minutes
from what seemed to be a scene in a movie. I was feeling like an
intruder, unwelcomed and at the same time experiencing guilt for my
successes in relation to what I was experiencing. I didn’t have to
live in a box, fight for a bench, and felt my pride would never let me
stand in line for food because I was starving.
their life trials these people faced everyday there was still evidence
of a hierarchy within the sub culture of homelessness. The real
estate may not belong to them legally, however, this area of street and
park was their home.
Trying to put myself in their shoes, I was thinking that if I were
homeless here how great would it be to have fresh food literally free
for the picking. One of the walls was going to be adjacent to a
basketball court. The initial mistake we assumed was that the
Edible Wall was something they wanted; yet we were met with resistance.
In the hierarchy of the residence of this particular park, we were
treading on something that was not ours. We had to actually step
back and re-think our approach; we had assumed that the edible wall, a
food providing wall with strawberries, cucumbers and more, would be
accepted with open arms.
from you and I, very few people in this world enjoy having something
forced on them. If we would have taken the time to do
preliminary interviews and engage the people we were trying to help, I
think the initial outcome would have been more accepted. Homeless
or not these people, this society, clan, whatever they are labeled,
still had feelings and a sense of ownership of the space we wanted to
use for their benefit. We had seen it as helping, and they had
seen it as intrusive and “How dare you tell us what we want!”
Edible Wall Growing at Cal Poly Parking Area.
Joyce and Candice eventually found four locations to accept 750 square
feet of the Edible Walls. This project would be the first of its
kind anywhere in the world. The concept was to be able to allow
anyone to walk up to the wall and harvest produce and eat it raw.
We wanted to bring the first walls to the sites already bearing fruit,
but implementation was much more difficult than just hanging up our wall
systems. We had to start the growing and where? We had to
have the panels delivered and installed, teach maintenance, irrigation,
and designate someone to be responsible for each project.
Logistically these edible walls are unlike a sedum green roof in that
they need much more water, trimming, harvesting, and are located on a
wall in downtown Los Angeles - this was the hardest planning project for
our team and all with minimal funding.
The first recruit was Hunter Francis from California Polytechnic
Institute (Cal Poly) in San Luis Obispo. Hunter and two graduate
students were willing to turn one of the parking areas into a place to
grow the Green Living Walls prior to installation. If you recall,
my kids started planting seeds and to this day we still plant some seeds
on the walls, however, it works best by starting with a 1” plug or
starter plant. So the wall units were laid out in the parking
area, filled with specialized growing media and planted with a
combination of seeds and starter plugs. The panels were allowed to
mature for six weeks and in August, 2007 we had 15 volunteers to help
load the panels in two refrigerated trucks driven and donated by another
local produce delivery company to downtown LA.
Homeless Participation; Right: Unloading the Truck.
Two trucks went
to four difference locations; it was very early in the morning and tight
moving the 18 wheelers around in the Los Angeles morning traffic.
And getting to the walls was a difficult task because of the distance
between the delivery truck and the mounting surface. For example,
Miguel Contreras High School we had to walk the panels almost 400
yards to the wall. At the
Los Angeles Food Bank we had some
of the workers help us unload the wall and the final two destinations,
Rainbow Housing Trust and
The Weingart Center - literally the center of homelessness - held the best surprises and
provided the start of an advanced
Volunteers helping with
a green, living, wall.
pulled up and a crowd started to gather out of curiosity; the crowds
were the same people we were helping. Many volunteers started to unload
the panels and the people in the crowd, without asking, simply jumped
right in and helped us unload. The senses of pride, self worth,
and empowerment are words I used to describe what they were feeling. One
participant told me, “It isn’t everyday a truck pulls up with fresh
tomatoes to be hung on a wall. So many times people help me and
this time I want to help someone else.”
As the panels
were unloaded and the crowd diminished there were four participants who
stayed with us. They expressed how they wanted to see these
tomatoes on the wall so I personally invited them to help. They
worked with us for the first half of the day and asked if they could
stay and come back the next day. This was a welcomed surprise - as
a former teacher I am very much for hands-on learning and when someone
asks to be taught or expresses interest in something you don’t say no.
That night I asked our installers if they minded that they remain on
call vs. installing the four walls. Of course they didn’t because
they, too, were volunteers.
A friend of
ours from New York, Kevin Kaye, and I worked with and taught these four
individuals from sun up to sun down for five days. They learned
everything we could teach them from start to finish; eventually they
installed the last wall without our help, including the irrigation.
They were not the only ones who learned something that week. We
found out that these were people are no different than we are. One
had been a film editor for Hollywood, another a contractor, the third a
business owner and the fourth a union carpenter. I thought in
silence to myself, “What and where did things go wrong to the point they
became homeless”? It taught me not to judge; I would have assumed
that it was due to drug addictions, laziness, or a life changing
disaster. For me the stigma was gone, these were no longer
homeless people; they were our neighbors and peers and now my friends
who only had a bad situation get out of control.
You may ask why
I was the one installing these walls in the first place? We did
have “installers” and they could have done the work and that would have
been the end of it. Our company is well rooted in moral values.
No one can ever come to us asking for a check as a donation, the answer
would be no. But if you want our help, we will provide you our
hand and sweat equity, money only goes so far and who knows where it
goes. What we experience as corporate giving allows us to learn
just as much as these four homeless people did during that week in
August. This is social responsibility at its best, I’m no
religious man but I do believe in teaching someone to fish so they can
feed themselves instead of providing a hand out.
What we have
done is produce a foundation that has provided a life changing
educational opportunity while providing high quality food in
environments that were at one time at the mercy of the distribution from
a traditional farm. Now instead of empty buildings and abandoned
parking areas there is the tangible and real application of an Urban
Farm, future educational opportunities, job creation and it’s all done
without specialized plastics, pumps, electricity, excessive water or
Volunteers and me; Right: Enjoying a beautiful new Edible
Volunteers celebrating a completed Urban Farming
Food Chain Green Wall in Los Angeles.
This is Vertical Farming changing the way we think
about agriculture and the relationship to urban inner cities. If these
four individuals were to be paid for their work there is a labor value
of close to $55.00 per man hour to install these walls and another
$20.00 per man hour to maintain them and an additional income
opportunity by selling the produce at road side stands in center city
less than 100 feet from where it was grown.
It doesn’t end here; this was a wake up to a much larger calling.
What if we can take what we have done and duplicate it throughout the
world? We can and did with easy to use, almost off the shelf raw
materials. What we did is scalable, affordable, and does not
require specialized equipment. The Urban Farming Food Chain also
provides additional learning opportunities to learn how to cook the
food, prepare healthy meals, job training and more.
"A" Frame Vertical
Gardening by GLT.
This experience has spawned an agricultural revolution - vertical
farming is no longer conceptual and the use of horizontal space is not
necessary to grow food. This technique of vertical farming method
food production uses the power of nature, traditional soils and is done
100% organic without the use of chemicals and pesticides. In just
the past year, products such as the Patent Pending Green Living™
Technologies “A” Frame are now available to grow 96 sf of food while
utilizing only 32 sf of minimal horizontal space, doubling and tripling
the yields per square foot and all in a parking lot or in a
Our relationship with Urban Farming has become a staple of our business
model for many years to come. We continue to work towards
developing new agricultural techniques, self help programs and
empowerment opportunities not just for the homeless but for ourselves.
There is much more to businesses than writing a check as a giving
program. It’s been a humbling experience to be able to impact so
many in such a short amount of time. I suggest everyone go out and
volunteer your time, as you, too, may learn something.
George Irwin, The Green Wall
Since the installation of the first Urban Farming Food Chain in Los
Angeles, there have been Edible Walls implemented in more locations such
as New York, California, Vancouver, B.C., and Hawaii with others slated for
South Africa, South America and Dubai.
Currently in progress,
Green Living Technologies has developed the GLT Innovations, LLC which
includes the GLT Institute providing green job training and job
placement in the future GLT Food Factories and GLT Farms, all utilizing
the Green Living Technologies Green Living Walls.
interested in sponsoring a link in the Urban Farming Food Chain, please
Green Walls as
Marketing Trends in 2009
By George Irwin, The Green Wall
All Photos Courtesy
George Irwin, unless noted
August 3, 2009
different than 2008, this has been a very busy first half of the
year with expos, workshops and conferences. The build up
Green Roofs for
Greening Rooftops for Sustainable Communities Conference, Awards
and Trade Show is always great, and to name just a few
coming up in the fall there are the
American Society of Landscape Architects (ASLA) Annual Meeting &
Expo in Chicago, the
World Green Roof Conference in Toronto, and
Greenbuild in Phoenix, not to mention the thousands of other
industry awards and trade shows held globally.
about the non-green roof/wall industry shows? Food,
vitamins, fitness, cleaning products, cars and thousands of
other companies trying to establish symbiotic relationships to
being green or those going green are out there promoting,
selling and engineering how to gain market share. And how
are companies attracting attention? What are they
doing differently to draw you in? Here are some of the
albeit eye-catching but less creative ideas I have seen - how
about that loud blower with the tube that goes 20 feet in the
air and waves frantically? Or the small flashing button
someone wears on their jacket to make you look or the obnoxious
personal favorite “made you look” ploy is the glamorous women at
trade shows who have no idea what product they are promoting.
On a larger scale I am impressed with the jumbo TV screens that
have taken the place of the common billboard and Times Square in
New York City has everything from a scrolling news cast, bright
lights, giant bottle caps to animated branding. What does
all of this have in common? Marketing. Doing things
bigger and better and in a way that has never done before.
Marketing includes branding, consumer awareness, client
relationships, pricing and more; this is nothing new, it’s a
multi – billion dollar industry. I found the formal
definition of ‘Marketing’ via Wikipedia to contain a minimum of
four definitions from just as many chartered institutes and
marketing associations that included everything from
advertising, selling, distribution, research, social sciences,
sociology, math, pre and post sale promotions……and more I won’t
list as it’s simply too long….UGH! Time out! I just
want a simple definition, yet apparently there is no such thing.
From personal experiences there are many newer marketing tools
like the ever popular email newsletter, blogs, Twitter, etc.,
which are all great for electronic interactions. But in
our real, physical world, what about the higher end signage and
branding? With the economic downturn and as tough as it
may be financially, the experts say to increase your marketing
budget instead of cutting it.
According to guerrilla-marketing expert
Levinson, "In times like this, people think the first thing
to do is to cut back on marketing to save money, but that's kind
of like ditching your wristwatch to save time. A down
economy is not a time to become low profile, or people will
wave in marketing and the trend we are seeing now is through
green walls, both permanent and temporary. Big business is
recognizing the marketing potential not just to attract
attention, but to attract positive attention to their products
and services. In a very early post I once coined green
walls as “Marketing Genius.” Now if I could only predict
the stock market like I did green walls.
Green walls initially focus on visual marketing (wait until the
next few paragraphs). Vision is one of the primary human
senses and the patterns we recognize to differentiate the world
around us become familiar until something new or unusual
interrupts the visual landscape. Visual marketing means to
kick it up a notch and break up these stale vistas.
may include seeing the combination of letters and words making
up this very article or the same buildings and scenery while
traveling to work. You’re putting ordinary symbols
together that are very familiar and, for the most part, can
become a blur of sameness. Case in point, the font and
color for this piece are very common, but add the following
“green wall” in all caps with bold font and a different color,
and it draws attention even before you can get to it: “GREEN
Left: Before, common façade;
After: 2,400 sf of vertical wall (coming in
September, 2009 at 1 PNC Plaza, Pittsburgh, PA).
same is true as we visually scan a room, office, cityscape, etc.
There is a common psychological expectation and response for
what are used to seeing vs. seeing something unexpected.
Over the winter I was at the National Restaurant Show in Chicago
and this became abundantly clear. Being involved with the
green industry it has been common for me to see nursery people,
green roofs and plants all together in one room, but the
restaurant show was a contrast. It showcased lot of
industrial, metal equipment and accessories, everything from
shiny stainless steel counters and coolers to copper cooking
pans and cutlery.
Speaking of contrasts, amongst all the inanimate stainless steel
there was one great contrast which really stood out, a living
booth. A company created a leafy green indoor paradise by
utilizing green walls and sod floors very different to the rest
of the show! The booth was actually promoting awareness on
how restaurants can go green and so they used highly textural
live plants in juxtaposition of the other cool, smooth surfaces.
The point is the booth was extremely unique and so distinct that
people remembered it.
Contrasting Booths at the National Restaurant Show
green walls is a tool that gains attention - add a brand to it
and the experience is now even more memorable. In fact,
for 2009 the Publisher and Design Editor for Greenroofs.com
included Living Billboards in the #10 category, Client-Specific
Boutique Greenroofs, for their yearly installment of the
Top 10 Hot Design Trends in
Living Billboard: "Garden Spots," New York City,
2008. This award winning design proposes to create
living “air gardens” on the unused backsides of New
York City billboards. The design team from TODO
Design and DAS Studios won first place in the iDA
Land & Sea Competition for their unique approach to
greening the city. Very eye-catching!
Living Billboard: "Billboards Made of Lettuce,"
2008. This unique growing outdoor garden billboard
was planted with green lettuce planted to form the
words “fresh salads” by Leo Burnett. It promotes
McDonald’s health-conscious menu items and won Gold
at the 2008 New York Festivals’ Innovative
green walls initially focus on the visual, but that is not
always true. Vision is not our only sense! Touch and
smell are two other very strong senses. I have seen people
walk up to large commercial projects and small trade show walls
touching and asking if it was real. Texture and smell are
as relevant to the overall project or marketing as the
aesthetics. Texture is used to create pictures and logos within
the walls. Remember the contrasting description between
the living booth and the stainless steel? The same is true
for custom branding embedded directly into the wall itself,
adding an entirely new dimension and contrast that breaks up
normal visual patterns.
Getting all the
attention at the Eastview Mall, Rochester NY
Green Wall w/ Basil
think for a second that marketing stops here, though.
Scent marketing is a science by itself. A classic example
is for home sellers to bake cookies when potential buyers visit
to enhance the sense of a cozy home. Going back to restaurants,
how about walking into an Italian restaurant and the first thing
you’re greeted by is a fresh face full of basil…growing on the
Italian is not your preferred choice. Then how about lemon
grass, sage, chives, mint or just about any scented herb?
All growing on the wall. I know chefs who greet clients at
their table, turn to trim a fresh herb from the green wall
in the dining area and then freshly dress up the customer’s
meal. How about serving dessert with the mint garnish
literally trimmed from a mini-herb wall right from your table?
I think it would be safe to say this would be a dining
experience with a personal twist to come back and enjoy again.
And why stop with restaurants? How about a relaxing spa
massage with humidity-infused, freshly snipped lavender or mint
from a green wall? These are true fresh scents through
natural air fresheners and aromatherapies with no Volatile
Organic Compounds (VOC’s) from artificial sprays and misters or
those little plug-in “fresh” scents.
Unlike many green roofs, you can see a green wall up close, and
green walls scream attention. No matter what the intention
is, marketing, function or environmental, the fact is there is
much more to green wall marketing than just a cool trend, and
we’re just seeing the beginning of their possibilities in the
for a marketing firm in a memorable Seattle lobby.
George Irwin, The Green Wall
Green Wall Research, Full
By George Irwin, The Green Wall
All Photos Courtesy
April 11, 2009
Updated April 26, 2009
reduction of urban heat islands, usage of fossil fuels, increased storm
water retention……..sound familiar? If you’re a green roof fan you
will recognize these are some of the benefits of green roofs.
Green roof data has a long history. What about green walls?
Some of the earliest research depicts the use of green façades as a
means to cool buildings by shading.
In reality it
was the grape that was planted close to the building. The vine
produced more fruit faster, it ripened with added sweetness and
produced an excellent wine with high alcohol content. With a long
history of facades, where is the modern data? More scientific
research is being done as I write. For example,
Green Roofs for
Healthy Cities announced a
formal research fund at the 2008 Greening Rooftops for
Sustainable Communities Conference, Awards and Trade Show in
Baltimore. I know of a few others that are more specific to
individual manufacturers. With all the available data on green
roofs, green walls are lacking.
Some of you may
recall a study published by Drs. Brad Bass and Bas Baskaran titled “Evaluating
Rooftop and Vertical Gardens as an Adaption Strategy for Urban Areas,”
(2003). In this column I include some of the paper as a pre-cursor
that identifies green walls and their ability to cool the walls of
buildings. Involved directly with many research opportunities, I
find the common question is relating green walls to green roofs.
How can green walls compare to green roofs in saving energy? Here
are some of the earliest modern references to green walls that are
compared to preliminary short term data that will provide the ground
work for additional long term studies.
According to Bass and Baskaran, "Higher than average temperatures within
city limits known as Urban Heat Islands (UHI) are a direct result of
replacing vegetation with typical urban surfaces also creates an
elevation of temperature relative to the surrounding rural or natural
areas. The UHI occurs because more of the incoming solar radiation
is absorbed by dark surfaces such as rooftops and pavement in the city
and reradiated as longwave radiation or heat.
certain temperature, the demand for electricity is inelastic.
Above this threshold, every degree C increase can increase electricity
consumption by 5%, increasing emissions of the fossil fuels required for
its generation. Although the UHI may be as small as 2° C, that may
be sufficient to move the temperatures above this threshold due the
additional demand for air conditioning and requirements for
refrigeration. The increased temperatures also increase the
problems associated with heat stress and the rate of ozone formation."
Vegetation can reduce all of these impacts. The focus is
vegetation reducing the UHI and thermal elevations is because of
evapotranspiration. Incoming solar energy that is used for
evapotranspiration cannot be absorbed and re-radiated as heat. Studies
in Oregon demonstrated that non-vegetated areas could exceed
temperatures of 50° C (122° F) in July while vegetated areas remain at 25°
C (77° F) (Luvall and Holbo, 1989).
Vegetation can also further alleviate air and water quality problems by
filtering pollutants through the leaves or the roots. In addition,
vegetation in urban areas has been shown to increase mental well being,
biodiversity and residential property values.
"Most discussions of the UHI focus on the temperatures of surfaces or
the canopy level UHI, which occurs at the level at which most people
live. We only feel surface temperatures directly when in contact
with these surfaces, but they heat up the surrounding atmosphere.
For the canopy level, the primary affect is experienced in the evening.
Heat from rooftops affects the temperature of the boundary layer or
upper layer of the atmosphere, the layer of the atmosphere extending
roughly from rooftop level up to the level where the urban influence is
no longer ”felt"" (Oke, 1976). This additional heating occurs
throughout the day and influences the chemistry of air pollution and
temperatures above the roof."
Oke (1988) found that temperatures in the urban canyon and temperatures
in the lower part of the urban boundary layer, are usually very similar.
Thus, higher temperatures above the roofs can affect temperatures at
canopy level, where we live, and in areas with only one or two story
buildings, the roofs may be at the canopy level.
"Reducing the rooftop temperatures would further reduce the use of
energy for space conditioning in both the summer and the winter.
In the summer, a typical insulated, gravel-covered rooftop temperature
can vary between 60° C (140° F) and 80° C (176° F) (Peck et al., 1999).
These temperatures increase the cooling load on a building in two ways.
Since the internal temperature underneath the roof is typically lower
than the temperature above the roof, the heat will always flow through
the roof into the building. In addition, modern high-rise
buildings are constantly exchanging the internal and external air.
Because of the high roof temperatures, the temperature of this external
air that is brought into the building’s ventilation system may be warmer
than the ambient air, requiring additional energy for cooling.
"Evapotranspiration from rooftop vegetation could cool the roof,
reducing the amount of heat flow into the building through the roof.
The lower rooftop temperature would also reduce the temperature of the
external air that is exchanged with the building’s air. The
temperature of this air could also be reduced if the rooftop garden is
designed so as to shade the intake valves." Summer temperatures as low as
25° C (77° F) have been observed. (Peck et al., 1999).
Most of the
above is taken from the publication of Bass and Baskaran, and some of the data is well over
10 years old. Ten years later the technologies, materials, and
design techniques have also evolved. There has been no slowing
down the green roof momentum and green walls are not far behind.
The focus to combat the issue of UHI was primarily on green roofs until
additional technologies were also being recognized for the ability to
cool the Urban Heat Island. The walls are heating up and
reflecting UV rays just as much as a roof top, depending upon the color
and surface material, location, etc. Green façades (trellis structures with
climbing plants) were utilized to shade the sides of buildings much in
the same manner green roofs were used for the roof tops.
catch: on average buildings have much higher wall-to-roof ratios in most
An even greater amount of space for vegetation may be available on the
exterior walls of the buildings in urban areas, and growing vegetation
on walls could create vertical gardens. Vertical gardens increase
the amount of vegetative surface in urban areas, increasing
evapotranspiration and evaporative cooling, and can be used for direct
shading as well. In comparison, green roofs directly affect the boundary
layer UHI, and vertical gardens can reduce the canopy level UHI.
Previous observations indicate that vertical gardens
do reduce the heat flow into the building, and their surface temperature
is lower than a bare wall, which is necessary to reduce the urban heat
island (Bass and Baskaran, 2003). A series of experiments in Japan suggested that vines
could reduce the temperature of a veranda with a southwestern exposure
(Hoyano, 1988). Vines were effective at reducing the surface temperature
of a wall. In Germany, the vertical garden surface temperature was
10° C (18° F) cooler than a bare wall when observed at 1:30 p.m. in
September (Wilmers, 1988). The study does not state how mature
the plants were. Theoretically speaking, the potential for
additional shading would be accomplished with with fully grown
Holm (1989), demonstrated a reduction of 2.6° C (4.7° F) behind the
vegetated panel. For a building consisting of two 10mm
fiber-cement sheets with 38mm of fiberglass insulation, a computer
simulation estimated that a vertical garden reduced summer daytime
temperatures on the surface by 5° C (9° F). These results are not
as dramatic as the cooling effect on a horizontal surface, such
as a roof, but given the amount of wall space in urban areas,
the potential impact of vertical gardening is expected to be
These results were utilizing green façades and the primary
method of cooling was shade and the process of transpiration
accounting for the movement of water within a plant and the
subsequent loss of water as vapor through stomata in its leaves.
Mentioned earlier were
two ways of cooling a roof top. The first is shading with
vegetated coverage and the second is through the process of
evapotranspiration to dissipate accumulated heat energy.
Technical breakthroughs have a few companies manufacturing and
producing Green Living Walls or Living Walls - defined as wall
structures that support rooted plant coverage. This is different
than a green façade that can be identified as having a climbing
plant at the base of a support structure. The majority of living
walls are media-based except for a single hydroponic wall. The
premise is that the media will also retain water available for
evapotranspiration. Utilizing the living wall, both shading and
evapotranspiration are implemented.
Many models exist that analyze numerous variables to determine
the rate at which water evaporates and creates a cooling effect. Let's keep it simple and provide tangible examples.
Since we established that vertical surfaces can be comparable to
horizontal roof tops, can we assume a living wall with the same depth
will provide the same cooling results, only vertically?
I would have to say "yes" as I leave myself open to debate and
welcome other opinions. Unlike green roof research, there is a
lack of defining green wall data. Green Roofs for Healthy Cities
has implemented a research program for living walls and green
facades. I have implemented thermal testing specifically for
green living walls and will be analyzing data after completion
of a 1-year study (July 2009).
The preliminary short-term thermal testing showed that a 3” (7.6
cm) deep green living wall provides similar results under the
same environmental variables as a green roof with 3” growing
medium depth. The initial test plot was painted black (behind
the living wall) to match the EPDM rubber membrane.
The preliminary short-term thermal testing showed that a 3” deep
green living wall provides similar results under the same
environmental variables as a green roof with 3” growing medium
depth. The initial test plot was painted black (behind the
living wall) to match the EPDM rubber membrane.
Temperature Comparison Test Results
testing shows an average surface temperature difference of 75° F (41.7°
C) between the exposed rubber roof and the protected green living wall.
This observation supports more advanced research. With more detailed
testing and longer trials comparing 3", 4" and 6" rooting depths, I feel
confident that the findings will show even better data as a direct
result of evapotranspiration and shading. The mentioned
preliminary study is being conducted in Rochester, NY with a short
cooling season. This study will be compared to other thermal
testing I will be conducting over the summer 2009 near Miami, FL, where
we expect the green wall’s cooling capabilities to rival that of green
roofs in locations with cooler growing seasons.
Hoyano, Wilmers, and Holm had recorded 10° C, 2.6° C, and 5° C reductions in surface wall
temperature utilizing green facades with shading as the primary means of
temperature reduction. Our initial observations indicate similar
thermal mitigation by green walls compared to green roofs.
hypothesize that medium depth, hydration layer, and rate of
evapotranspiration each contribute to reduced wall surface heating.
However, the extent of these and other influences remain an open
question until ongoing and future research can provide much needed data.
The eventual comparison will be between green façades and living walls.
George Irwin, The Green Wall
Bass, B. and B. Baskaran, 2003: Evaluating Rooftop and Vertical Gardens
as an Adaption Strategy for Urban Areas: Impacts and Evaluations
Progress Report. April 1, 1999 – March 3, 2001.
Holm, D., 1989: Thermal
improvement by means of leaf cover on external walls - a simulation
model. Energy and Buildings, 14:19-30.
Luvall, J.C., and H. R. Holbo, 1989: Measurements of short-term thermal
responses of coniferous forest canopies using thermal scanner data.
Remote Sensing of Environment, 27:1-10.
Oke, T.R., 1976: The distinction between canopy and boundary layer urban
heat islands. Atmosphere, 14: 268-277.
Nakamura, Y. and T. R. Oke, 1988: "Wind, temperature and stability
conditions in an E-W oriented urban canyon," Atmospheric Environment,
Hoyano, A., 1988: Climatological uses of plants for solar control and
the effects on the thermal environment of a building. Energy
Wilmers, F., 1988: Green for amelioration of urban climate. Energy
and Buildings, 11:288-299.
Note: See the
Baskaran, Bas and Bass, Brad (2003) "Evaluating Rooftop and Vertical
Gardens as an Adaption Strategy for Urban Areas,”
References Page listed
at the National Research Council Canada - Conseil national de recherches
Green Walls and
Indoor Air Quality
By George Irwin, The Green Wall
All Photos Courtesy
George Irwin, unless noted
January 19, 2009
Compare this wall to the one below!
a relief it was to escape inside a friendly tropical office from the
mounds of snow we have here in the Northeast and see lush green
vegetation protruding from a wall deep into the long hallway.
It seemed as if it were a mirage as I walked
closer to the wall, as a feeling of warm and moist air filled the
corridor, removing my thoughts of the extreme cold outside back home.
If you’re lucky enough to live in a moderate climate during the harsh
northern winters, you will more than likely have to endure a rainy
season, but at least it’s warm.
This is exactly what happened to me after a
visit to San Pedro Sula in Honduras a few weeks ago - the moist humid
air was a welcome relief from the dry cold winter of the Northeast.
Green Living™ Wall in Tropical Honduras;
Photo Provided by Techos Verdes
Sick Building Syndrome and Indoor Air
In the early and mid
1900's, building ventilation standards called for 15
cubic feet per minute of outside air for each
building occupant primarily to remove body odors.
Back to reality, I’m from Rochester, New
York, and we are currently buried in snow and cold. The wall I was
standing next to in Honduras offered a reprieve from the reality of the
weather outside. During all seasons, occupants inside
offices and homes alike are suffering from dry air - from cracking skin
to coughing and congestion from people with whom we share the space.
Actually, these are some common symptoms described by the U.S.
Environmental Protection Agency which are indicators of Sick Building
Syndrome (SBS). Other more severe indicators include: dizziness
and nausea; difficulty in concentrating; fatigue; and sensitivity to
What causes SBS and how can adding green
walls help? The costs and potential payback are detailed in this
article for the commercial property owner, designer, or architect who
will be able to utilize this to inform clients.
Multiple sources contribute SBS to having a
direct relationship with indoor air quality (IAQ). Buildings,
especially newer construction, are built to be air tight to provide a
comforting environment with heat and air conditioning. The adverse
result is the lack of air circulation and proper filtration.
Inadequate ventilation is also a result of HVAC equipment that is either
outdated or lacks sufficient means to distribute air. The
following are deemed by the EPA as the leading causes of SBS: inadequate
ventilation; chemical contaminants from indoor sources; chemical
contaminants from outdoor sources; and biological contaminants. 2
Solutions and Economic Considerations of
The solutions to remove the compounds may
include pollutant source removal or modification, an effective approach
when sources are known and control is feasible. Examples include
routine maintenance of HVAC systems, e.g., periodic cleaning or
replacement of filters, and increasing ventilation rates by utilizing
HVAC systems, at a minimum, to meet ventilation standards in local
building codes. However, many systems are not operated or
maintained to ensure that these design ventilation rates are provided.
Air cleaning can be a useful adjunct to source control and ventilation
but has certain limitations.
Indoor Green Living™ Wall Freestanding Unit with VOC
removing Peace Lily, Janet Craig, Pothos & Dracaena.
Particle control devices such as the typical
furnace filter are inexpensive but do not effectively capture small
particles; high performance air filters capture the smaller, respirable
particles but are relatively expensive to install and operate.
Mechanical filters do not remove gaseous pollutants. Some
specific gaseous pollutants may be removed by adsorbent beds, but these
devices can be expensive and require frequent replacement of the
adsorbent material. In summary, air cleaners can be useful, but
have limited application and can be expensive. According to the
EPA, clearly the mechanical means of removing toxins, particles, and
Volatile Organic Compounds (VOC’s) from buildings are options, but none
claim to be the solution or 100% effective and are costly.
However, there is strong evidence on a more
natural solution. This natural or holistic approach to cleaning
indoor air can be as simple as adding the ecosystem that is responsible
for creating fresh air to begin with: the indoor green wall. The
indoor green wall eco-system is a very complex order that has the
ability to change; it’s a built in survival mechanism. Plants can be
resilient and what may be toxic to one species is a source of survival
for another. VOC’s have been the focus of many studies in recent
years and it is now evident that data concludes over 80% of VOC’s can be
removed by plants. 3
Interior Green Wall; Photo Courtesy Elevated
NASA (1984) published one of the first
studies demonstrating that plants can help to remove VOCs from sealed
indoor environments (Wolverton, n.d.). 4 Later researches confirmed
these findings and also suggested that micro-organisms of the soil might
also be involved in removing toxic VOCs. Certain plant species can
remove up to 100% of the air-borne VOCs within a 24 hour period.
Some of the top performing plants include: Howea forsteriana
(Kentia palm); Spathiphyllum wallisii var. Petite (Peace Lily);
and Dracaena deremensis var. Janet Craig (Janet Craig Dracaena),
(Burchett et al, 2001). Most recently (March 2005), The Plants and
Environmental Quality Group at the University of Technology in Sydney
concluded that both the plant metabolism and the soil microorganisms
are involved in removing the VOCs from the air. 5
Prior to the University of Technology
(Sydney), other studies were conducted in controlled laboratory test
chambers. In an authentic setting the findings showed that plants
work to remove VOC’s in a real life situation. The data
demonstrated that both floor and table specimens, in air conditioned and
non-air conditioned space, were effective in reducing the VOC’s to ~100
ppb (parts per billion) - regarded as acceptable using only 3 - 6
specimens in 10” and 12” pots.
Green Wall at the University of Guelph-Humber in
So it's obvious that if you are considering
adding vegetation, plants or a green wall in your building you don’t
have to have an interior jungle and masses of plants to obtain results.
Conclusions of both the field study and controlled studies strengthen
the conclusion that “The potted plant microcosm is an effective, self
regulating indoor-air-cleaning-system for ‘bioremediation of indoor air
or phytoremediation of indoor air quality," (Burchett et al, 2005).
The plants are also self regulating; they automatically kick on when the
VOC levels reach 100 ppb. 6
We know that cleaning the air can be done
mechanically and biologically. The mechanical means would need to
include at times cumbersome and costly equipment, require
additional space, potentially cause an acoustic burden on the immediate
work or living space, and may not prove to be 100% effective. The
mechanical means provides one service without any additional benefits.
Let's premise that the data is a direct
reflection on using a soil-based potted plant; in theory then it is
assumed that for comparing green wall systems, a soil-based green wall
would need to be considered for similar performance. The data
suggests that the VOC’s removed are a direct result from microbial
reactions at the root level. Biological means of adding plants has
proven to rid the interior space of VOC’s to an acceptable level.
Adding plants also offers other benefits that include aesthetics,
raising humidity levels to the air during the dry seasonal months, and
they also offer opportunities of marketing value.
Commercial Floor Space Comes at a Premium
The studies from the University of
Technology used specimens of table and floor units / potted plants
containing Janet Craig Dracaena (Dracaena dermensis). The
study needed to utilize valuable floor space to house the pots. In
the United States, on average retail and office space is $25.50 per sf
(New York City averages $38.00 per sf as a high and Iowa averages $13.60
per sf as a low)
7. Allowing for an area of sufficient floor space
that would create the desired results of cleansing the air of VOC’s and
provide an aesthetic value would require six potted plants @ 10” – 12“
deep, or the equivalent of 35 square feet.
12” Potted Plants, Figure 1
From a monetary perspective, due to its
vertical nature a green wall is less than half the cost of occupying any
retail floor space, assuming the cost per sf in rent noted above is
accurate. One retail store and green wall owner recently said:
“I’m reluctant to find the money to spend
on plants that take up floor space in our retail store when I would
rather have merchandise; it’s just simple economics. Since we
installed our green wall not only has our store been noticed but the
area has been more inviting and the comments from our customers have
been nothing but positive.” ~ Joe Edmond, owner of Green Acres
Garden Center in Greece, NY.
Floor vs. Wall Space: Get More for Your
The value of implementing such an
arrangement would equate to sacrificing a conservative 35 sf of floor
space x $25.50 per sf would require a monetary expenditure of $892.50 a
month on potential floor space that could be otherwise be dedicated to
another desk or, in a retail space, more merchandise on the floor.
Looking at the long term expense based on a yearly value, $892.50 per
month for floor space x 12 months is $10,710.00 per year for an
aesthetically pleasing and functional area of potted plants . (*For the
purpose of this column the cost of plant maintenance and other utilities
were not considered and the figures mentioned are generalized as a base
line comparison to evaluate other budgetary options.)
The current market for an indoor green wall
has increased to rival that of an exterior wall. The cost per sf
has ranged from $100.00 to $175.00 per sf depending upon the system and
the plant material. Based on our estimated yearly cost to allocate
35 sf of floor space containing potted plant material, a more economical
option would be to consider a green wall. Utilizing the simplest of
green wall systems and the lowest of initial cost per square foot, the
wall could be as low as $3,500 for the same 35 square feet of floor
Now, in reality that original floor space of
35 sf was not 35 sf of complete “Green Vegetation” primarily due to the
voids of the potted plants. (See Fig. 2) The green wall,
however, would provide a canopy that is 100% equal to that of the
design. That same 35 sf of floor space on a wall is actually 35 sf of
“Green Vegetation.” There are no voids and in theory as an owner
of the green wall the air cleaning and VOC removing benefits, according
to the previous data, would provide an even more effective return on the
investment - strictly speaking about the green area you would get more
“Green Vegetation” for your investment.
More Tangible Benefits
On a lesser note, other opportunities
present themselves as tenants, clients and other building visitors with
green walls extend comments like, “I wish there was more of these
plants,” “Cool,” “Are they real?”, “The room smells so much better,”
“What a relief from the cubicles!” The result is people are
talking and presenting an opportunity to reflect positively about the
new green space. After installing a green wall, one major retailer
had increased traffic due to the attention resulting in higher margins.
Other tangible benefits include noise reduction, improved productivity
and lower absenteeism, to name a few. According to Environmental
Building News, a return on investing in plants would result in an annual
savings of $975.00 per employee, a return on investment of 995%. 8
Environmental Building News, Vol. 13, No. 10; Figure
Green wall design and planning require
mechanical functions as well as biological. As a designer, one of
the key components to consider is how the wall will be irrigated.
This is the number one evaluation, not any less important than the
lighting, maintenance and system type but if the wall is to include an
automatic irrigation system from a constant source of water (a direct
connection to a main water line), we strongly recommend an overflow
built into the irrigation catch basin. To no fault of any one
system or any system installer, if there is a mechanical failure within
the irrigation components the water will be diverted into the overflow
preventing any flooding. Another option is to have a reservoir of
irrigation simply re-circulated throughout the wall. The best
advice is to talk to the system manufacturer or installer about your
In previous articles I have written about
various green wall systems, definitions and applications. I’m
going to premise a topic that I will eventually write about at a later
date, but currently we see an opportunity to integrate mechanical and
biological means of using green walls as a bio-filter. When
designing a green wall as integration into the building there is much
less of a chance for the system to be value-engineered from the project.
Design the wall as a part of the building and the building's ventilation
system is a must-have not just for aesthetics, but for overall
Beauty and Function
Green Living™ Walls are beautiful living machines.
At first, it is always the breathtaking
beauty of a green wall that is the focus. Indoors, the wall
provides a reprieve of sorts from unfavorable seasonal elements.
Yet there is more to it than that. Studies have proven the
effectiveness of potted plants to remove harmful VOC’s from our
dwellings and workplaces. Green walls would provide an opportunity
to add an increased vertical canopy of “Green Vegetation” per square
foot in comparison to potted plants on the horizontal plane of the
floor. With sky high retail leasing costs, monetarily speaking the
green wall is shown to be the economic choice with added benefits to
increase marketing potential, employee productivity, preventing
absenteeism and simply provide an un-measurable benefit we call the “Wow
Next time you’re indoors and you're feeling
tired, have a head ache or dry itchy skin, think about what adding
soothing, living, breathing plants to a space can do for you, the people
around you, and the environment.
George Irwin, The Green Wall
5. Wood, R, Orwell, R, Tarran, J, Burchett, M, 2001, Pot-plants really
do clean indoor air, Nursery Papers, NGIA
Successful Maintenance on
By George Irwin, The Green Wall
All Photos Courtesy
George Irwin, unless noted
October 7, 2008
many of us the summer is almost gone except for the occasional spike in
temperature - the last long rays of sun and the ever changing colors of
explosive reds, oranges and yellow leaves are upon us. For others
the change of season is a minimally noticed drop in temperature and a
little less sunshine; for others it’s the rainy season. No matter
where you live, some type of change is inevitable.
As our green walls change how do we maintain them and ensure their
success? As you may know, "Green Wall" is used as a global term
for both living walls and green facades, for definitions refer to “An Intro to Green Walls and Green Roofs: Living Architecture at its Best
- Green Walls Part I Nomenclature.” We will talk about
maintenance variables that will affect the changes and the “How To”
application of maintaining green walls.
Variables of Maintenance.
A long overdue topic, I apologize for the
limited writing schedule and to talk about exterior maintenance may be a
few weeks late for those in the regions experiencing extreme changes
from summer to fall, but nonetheless maintenance can be defined by using
many variables. The five topics to maintaining a green wall we can
clearly identify as: location access, structural inspections,
irrigation, and drainage and plant maintenance. For a formal
maintenance plan, our commercial maintenance technicians utilize our
standard task of events or a simple checklist for all five variables on
a monthly basis. We refer to the checklist as a preventative
Before we dive right into the maintenance, a
reminder that the non-vegetated components, whether part of a soil based
modular system for a living wall or a cable / modular trellis system for
a green facade, are mechanisms to hold plants in place and to offer the
basic needs for plant survival. Rethink a simple potted plant. (I
have referenced this point in other writings.) The pot, no matter
how large or small, clay, plastic or metal, is a holding mechanism for
the plant. Traditionally, the pot is filled with a growing media
that can support a root structure, hold nutrients and when placed in the
correct amount of light and provided with enough
will usually survive.
If the pot contains a plant that needs sun
and you keep it in the shade and it does not survive, do you blame the
pot? The point is to choose a plant type that is relevant to the
sun aspect and microclimate of the green wall structure and therefore
conducive to the environment in which it will thrive. Back to the
case of the potted plant, can we really blame the pot if the plant fails
or doesn’t perform? Or should we rethink our choice of plant
material relevant to the needs of the individual plant, its environment
and the green wall mechanism? The point is green walls are simply
tools that allow us to host the living plants and help sustain vertical
growth, so don’t always blame the system for plant failure: first
evaluate the needs of the plants, plan your maintenance and plant
characteristics for survival accordingly. Although not all green
wall products are created equal and some do a better job of maintaining
plant health, most can be constructed of various materials such as
metals or plastics and offer a variety of options including depths,
which can all be taken into account by the designer.
That simple statement, “First evaluate the
needs of the plant” will lead us to the components for the plants'
survival…and ongoing maintenance. The plant world can be difficult
for the untrained botanist, so read the plant tags carefully prior to
purchasing or stand by the advice of the green wall manufacturer.
Each plant species has a list of characters that depict what the ideal
conditions should be. Characteristics can be identified as what
describes the plant. It may include phrases such as, “A rapid
growing ground cover that can turn red, bronze or brown in full
sunlight.” On the tag look for key words such as “sun” and
“water,” “heat and drought tolerant,” “needs constant moisture,” “fast
growing,” “potentially invasive,” and “hardiness zone.” These are
very important buzz words that describe the plant, what they need for
survival and will define the maintenance needs! We
would have to write a lengthy book in order to decipher all the possible
maintenance topics for individual plant types.
Physical Advantages on a wall.
When it comes to plant material in a green
wall, there are no secrets. The same plant in the green wall
has the same requirements as if it were planted in any horizontal plane.
The green wall, however, does provide some physical advantages.
The green wall provides an ergonomically advantageous position to
working in the vertical plane. This is especially true when an
edible crop wall is installed.
With crops, it is uncommon for the wall to
be above six feet high so it is easy to work on by standing in an
upright position, unlike traditional vegetable gardening where you
are always bending or kneeling. The green wall panels can also be
planted at a height comfortable for almost anyone making green wall
panels ideal for healing gardens, assisted living activities, children
and other physically disadvantaged scenarios.
to Access a Parking Garage.
We identified the five components to
maintaining a green wall to include location, structural inspections,
irrigation, drainage and plant maintenance. Although maintenance
is conducive to the plant type, the five headings are common threads to
any of the green walls.
Location in this sense is defined as the
physical area the wall is located. For example, is the wall behind
a secondary structure, is the wall only on an upper location of a
building or is the wall fifty feet off the ground? No matter what
the plant type, the first item of consideration is how to access the
green wall. Usually a similar method used during the installation
would be ideal. If the installer used a scissors lift or a man
lift the same equipment would be acceptable for major maintenance such
as plant replacement and major pruning. For general service and
site visits a ladder may suffice.
It is recommended that any of the green
walls be approached from a preventative methodology. The fact of
knowing the potential issues that may occur allows planning maintenance
around these issues, creating a simple task analysis and level of
hierarchal importance. Even the most experienced installers are
not exempt from mechanical failure so check your waterproofing and
penetration methods. In addition, if you are a customer or client
of a green wall manufacturer/installer, question these methods and ask
for specific details - remember that water will find the smallest
penetration. The structural bracket assembly on some systems is
very complex and warrants an in depth inspection, while others are
designed with simple functionality allowing for simple physical
performance and free water and air flow behind the green wall.
Left: Ladder used for an
indoor installation; Right: Scissors Lift.
Upon accessing the wall the first order is
to visually inspect the structural integrity of the mounting mechanism,
the waterproofing, if any, and the interior wall (for any signs of
moisture). For trellis and cable systems check the penetrations of
the anchors, spacers, and supplementary equipment in addition to the
The second order of events is to operate and
visually inspect the irrigation system. Some items to look for
include: clogged emitters, leaks at the coupler and connections and
small drips within the irrigation manifold. At this time it is
ideal to remove and clean or replace the filter or screen from the drip
irrigation system. This will prevent any sediment from entering
the thin tubing of the drip line creating clogs and emitter
malfunctions. The irrigation is easier to assess with a trellis or cable
system assuming the plant and the root system is at the base of the
mechanism used to support the climbing plant. The irrigation, no
matter a bubbler, soaker, drip or other low volume technique, should be
working to the original specification. It is also a good idea to
check the mechanical components such as the timer, zone valves, screens
and any connections.
Left: Greenscreen; Right:
Stainless Steel Anchor
A ccessing the irrigation for inspection.
Drip Irrigation Filter
During the irrigation inspection is also the
opportunity to check all the connected drains that collect the excess
irrigation and rainfall. No matter the location, interior or
exterior, a drain is essential to prevent water collection in the event
of a heavy rain or an irrigation failure. If the irrigation is
left on or becomes the victim of a faulty irrigation zone valve, there
is the possibility of the water overflow. The drain acts as an
overflow thus inspection of the intake must be part of the inspection
process. Materials such as dead leaves, soil, mud and even public
garbage have been removed from the irrigation drains!
The last order of inspection includes the
actual plant material. As mentioned earlier each plant has its own
maintenance requirements. A common maintenance requirement for
exterior green walls is to weed the wall. In this step, the
trellis and cable systems are more susceptible to weed growth since the
area the climbers are planted is on the horizontal surface. Unlike
the soil based green walls, weed seeds have a harder time rooting on a
vertical plane. Nonetheless, weeding is a common practice in all
Other common practice includes the physical
inspection of all the plant material. The visual health would be
obvious - disease, dieback, dead foliage and the noticeable and
acceptable levels of overgrown plants. It is common that some of
the indoor plants suffer yellowing leaves that can be easily pinched or
some climbers may become woody and can this can be solved by pruning.
It is at this time that the plants can be pruned, trained and cleaned.
Interior plants may require a dusting to
keep them healthy. After wiping any dust from indoor plants, you
can also apply a thin coat of a non-toxic plant shine to bring out the
plant colors and textures. This is also the time to inspect for
any erosion or media loss and the look of the non-vegetated component of
the product itself. Look for cracking, and in some green walls
there is a growth media bag that may require replacing. On the
exterior, the metal-based products are not susceptible to expansion and
contraction nor suffer from the heat and cold of the elements and
exposure to the sun. Also during the plant maintenance
checkpoint, inspection of the structural integrity of the wall mechanism
may be easier. This is an opportunity to see the internal portions
of the green wall that are usually covered by foliage!
Left: Fungus development
due to improper watering; Right: Leaf Shine product
Finally, as a miscellaneous item, if the
green wall system has artificial lighting this is a good time to check
the bulbs for replacement. With a planned preventative maintenance
program the physical structure and integrity should be inspected on a
monthly basis. Irrigation operational failures will be more
obvious since the plants will be on the decline, and leaks could become
a costly event.
Supplemental Indoor Lighting is like jewelry, accessorizing
and highlighting the green wall's best feature - the plants!.
No matter if you are a do-it-yourself green
wall owner or a professional maintenance technician and installer,
preventative maintenance will retain the safety and integrity of any
project, plus add years of sustainable beauty to any wallscape.
George A. Irwin,
The Green Wall Editor
How Does Your
By George Irwin, The Green Wall Editor
All Photos Courtesy George Irwin unless otherwise noted
peppers on the vine.
early Spring is normally our busy show season and between the
Go Green Expo
NYC and GRSC in Baltimore, it is great to be back home. Beside the busy
spring show season it is also time to garden! Personally, my gardens have
become my time to relax, and even better an opportunity to involve my
family. The kids help plant and my wife makes jam and pickles from what we
Since 3,000 BC families produced crops for their own consumption and some
marginal barter. In 1840, 69% of the labor force was farming, in 1930 it was
21% and in 1990 only 2.6% of the labor force is farming (www.agclassroom.org/gan/timeline/index.htm). There has been an obvious decline in farming in North America since the
1800’s. Before we talk about green walls I want to review some key points in
history about American agriculture.
Victory Garden for the cause was patriotic and sustainable.
From 1939 to 1945 the world was at war, and Americans were asked to divert
materials and efforts to the war effort. At the time this was a call for
self-reliance, recycling, and conservation of raw materials. Sounds like
another definition of Sustainability … Compare the circa 2008 vs. the 1940 definition of
self-reliance, amazing how history repeats itself. The public was encouraged to
plant “Victory Gardens” in all shapes and sizes. “Nearly 20 million
Americans answered the call. They planted gardens in backyards, empty lots
and even city rooftops,” (http://www.livinghistoryfarm.org).
spot will do.
According to the U.S. Department of Agriculture an estimated 20 million
victory gardens were planted. Fruit and vegetables harvested in these home
and community plots were estimated to weigh 9-10 million tons, an amount
equal to all commercial production of fresh produce. The program made a
difference except after the war, the promotion of gardens stopped and the
commercial agriculture industry was not prepared for the demand, creating a
shortage of fruits and vegetables. During these times of urban gardens there
was also a significant decrease in transportation going to and from the
As I write it makes me realize that either my wife or I are at the
grocery store at least 4-5 times a week for bread, milk or some type of
produce. What if we would simply grow all of our own produce and eliminate 3
trips to the store? As the farming labor force decreased and the urban farms
changed so did agricultural technology, including the introduction to
pesticides, machinery, seed altering genetics and growing methods.
pickles and strawberries for jam grown at home in the Green
Let’s go back to basics; you don’t need a plot of land to maintain your own
crop-producing gardens. With evolution and urban development, the removal of
fertile land was replaced with concrete and buildings and there arose
alternative ways to produce crops - you guessed it, green walls for crop
production. As per my last article it’s not all about the “Outer
Beauty…..it’s also the Inner Function.”
My wife is a traditionalist and we prefer not to purchase pickles, jams and
jellies; we do our own canning when possible. In fact, we grow our own
strawberries for strawberry jam, harvest our own salad and spinach and even
grow thumbnail carrots, squash, cucumbers and more.
Re-visit “Green Wall” (Green Walls Part I) as a global term used to
reference a variety of vegetated wall surfaces. Within the term “Green Wall”
we have two specific categories, Green Facades and Living Walls.
• ‘Green Facade’ or facade greening features a training structure that
support vines or climbing plants growing upward from the ground away from
the building (GW101, 2008).
Green Facade can now be dissected into two additional categories of product
• A multidimensional, welded wire trellising system;
• A variety of stainless steel cable and mesh systems.
Both systems support a variety of climbing plant material, can be
customized, and some are available in a variety of colors.
• ‘Living Wall’ is part of a building envelope system, comprising
pre-vegetated or planted on site panels containing plants, growing medium or
liquid nutrient installed in or on a frame, secured to a structural wall, or
it can be free standing (GW101, 2008).
Living Walls can also be migrated into two distinct categories:
• Hydroponics wall which uses recirculation water to deliver nutrients
directly to the roots of the plant material;
• Soil or growing media based walls. T hese walls are made up of a variety of
modules that retain growth media to support plant material.
You want to have a vertical garden, what system do you use? The question is
for you to question or talk with one of the manufacturers mentioned. When I
lecture about green walls I make it clear each system has their limitation;
each has pros and cons. Many features include plastic vs. recycled metals,
powder coating, growing media depths, drainage, watering systems, mounting,
maintenance and more. The common point is that when vegetation survivability
issues arise, the system itself is not to blame for plant failure.
Look at the system just as you would a terracotta pot. If you plant the
correct plant in relation to the pot, allow for proper lighting, nutrients
and care for your plant, it will thrive. If the basic needs of the plant are
not met or the plant is not right for the pot and the plant dies, do you
blame the pot? The same hold true to the green wall systems. You need to
choose plants that are conducive to the environment and care you apply in
relationship to the systems limitations.
The cable and wire mesh systems (Greenscreen, Jakob, CarlStahl) would be
more then adequate for climbing grapes, beans and supporting tomatoes, but
require an area below to support the root structure. Without a planter or
space requirements these systems are limited for vertical crop production,
unless the plant is a climber. Some of the living wall systems have more
limitations then others.
The standard ELT living wall panel has a 2.25”
depth and would be best suited for fast growing leafy greens and some
shallow rooted herbs that can be harvested during the early season. The
Green Living™ Wall by Green Living™ Technologies offers a wide range of
planting depths from 3” to 6” and has shown long term success with
everything from tomatoes, cucumbers, zucchini, carrots, eggplant,
strawberries, peppers and even watermelon. Both systems can produce edible
foods with the use of growing media supported on a vertical surface or free
Living Wall Panel; Right: Green Living™ Technologies
Making a choice of systems for your garden may be dictated by the area you
have to work with, and most of the systems are very flexible from a design
perspective. Greenscreen will customize the project to specification; Jakob
and CarlStahl are very flexible since they are cable systems and can be
assembled with average carpentry skills to meet any dimension. The ELT
system consists of a single plastic 20”x 20” panel that can be cut
horizontally. Measure carefully because cutting the structure vertically
will remove one of the side walls and irrigation will flow outside the
structure, so try to keep your measurements of the ELT panel even in order
to prevent cutting them vertically. The Green Living™ Wall has very flexible
dimensions and has standard stock in 1 foot increments and they can
customize any other measurement or curve you request including planting
depths from 3”, 4” and 6”.
Living Wall Panel with Leafy Greens; Right: Strawberries for
jam in the Green Living™ Technologies standard 4” depth.
Other options for growing vertical or at least elevated crops can be
demonstrated here using an old cat litter container with a hole drilled in
the bottom and painted green. The owner also planted Basil in the top. Special thanks to
www.marshalllee.net for sharing.
litter bucket-turned vegetable planter! Source:
Here are some examples of some of year's Irwin family's crops including
watermelon in the lower left hand side of the picture on the left. In the
past we found that the following can also hold themselves on the wall
without any problems or soil loss: tomatoes, peppers, leafy greens,
strawberries, herbs, thumbnail carrots, and dandelion.
In addition to the above examples, the following is showing a 100% success
rate with the help of a rack system under the panels to support the fruits
which include: watermelon, zucchini, cucumbers and squash.
Cucumbers at 9 weeks; Right: Tomatoes on the vine with GLT.
is a snap on a wall.
How about growing your own wheat grass? In my travels I found energy shots
of wheat grass selling for as high as $9.00 per shot. The truth is, you can
grow your own for pennies. The picture at left is a juice bar that has panels
of wheat grass growing out back while the one below is in the store is cut for use in
a variety of energy drinks and smoothies.
If you grow
it, you know it!
How does your garden grow? I hope you enjoyed these gardening ideas,
agriculture history and the rejuvenation of what I like to call the
“Sustainable Garden” instead of the Victory Garden.
Remember that each
system has various limitations, space consumption, potential mounting
possibilities, and applications as some units can be indoors. Even the
material it is manufactured from can play a role in a successful vertical
garden. It's not rocket science if we can grow our own produce, especially
during the geographic growing seasons, and if we could we eliminate trips to
grocery store, what would the residual results be? How much in gas could we
save? How much carbon can we offset? And the issue of food security would
rest with us at home.
Go out and garden - the worst thing that can happen is you end up with great
organically grown tomatoes and you spend time with your family doing it.
George A. Irwin,
The Green Wall Editor
Green Walls: Outer Beauty, Inner Function
By George Irwin, The Green Wall Editor
All Photos Courtesy George Irwin unless otherwise noted
As a child I was mesmerized by the bean seeds starting to poke up over the rim of old cafeteria milk carton that had the top cut off. I clearly remember my teacher lining up the milk cartons, mostly chocolate, along the window sill. As the week went on the mass of bean seeds look like a single carpet - I thought that was neat. And as a teenager I always admired the clean cut and straight lines of a professionally manicured lawn. Seeing the dark and light striped green color variations of the outfield grass I would ask myself how they did that - and I thought that was cool. As a young landscape entrepreneur the site of mass annual plantings, over grown trellises and displays of natural wild flowers would make me stop and look, and that too, was pretty awesome. These are all very specific things that caught my attention.
Touchy, feely and gorgeous in
Rochester, NY using Green Living Technologies, LLC;
Design by Pietro Furgiuele.
These visual experiences are all related to color, shape, texture and presentation; the point is it was eye catching. You don’t need to be a psychologist to realize that visual affects are an attractant and at times stimulating. Of course there is more to just visual attractants than plants; in fact, anything can be a visual attractant depending on what it is and who it is perceived by - but green walls are different, and I haven’t met anyone yet who didn’t think a green wall wasn’t “cool.”
Here we will discuss the use of green walls as visual attractants, artistic expressions, marketing campaigns and one of a kind pieces of art. Although most will find the green wall itself a work of art, you have to look beyond the initial beauty to see that there is also environmental and economic function.
In my last article, “An Intro to Green Walls and Green Roofs: Living Architecture at its Best,” we left off with the understanding that seeing plant material on a vertical surface stimulates curiosity and verbal excitement with words like: Cool, Wow, Neat, Different, and sometimes even words of disbelief: “Is that real?” It is these same people that are bringing the green wall to the attention of others with expressions like, “Look at that, Isn’t that neat, and Check this out;” they express a call to action that recruits others to share the visual experience with them. The Austrian designer Friedenreich Hundertwasser could be considered the modern artist and visionary who promoted the concept of living vertical architecture, and even to this day visitors are amazed at his integration of vegetation and architecture on green wall and greenroofs. See some of his work green wall below:
Hundertwasser-Haus, Vienna, Austria: 1977-1986; Photo Copyright Glenn Bristol;
RIT Green Living Wall™
A recent example came from a project at a much respected college, Rochester Institute of Technology (RIT). A small monolithic 100 square foot Green Living™ Wall system, nothing of vibrant color, was being installed in a brand new LEED™ certified building there. If the installer hadn’t tied off caution tape, students and faculty alike would have walked right up to where the installer was working to touch the wall. In addition, those same passers by came back with more people to show them, and the audience soon multiplied.
Right now, 100% of our calls about green walls come as a desire for a cosmetic addition to an indoor space or outdoor facade. But, it is also becoming more prevalent from our other business partners and corporate clients that incorporating a green wall can also be a stoke of marketing genius. My inaugural article also described in brief about the Anthropologies green wall in Huntsville, Alabama. One of the unanticipated benefits about that green wall is that it attracted people resulting in an increase of retail traffic. Since then, we are not the only ones who have realized the marketing potential; we have been working on three additional green wall projects for the same company, and they, too, realized the impact.
Lexus and Pangea Organics' “Nurture Nature” event specialty GLT display.
Earlier this year we were contracted by Lexus and Pangea Organics for the NYC kick off event “Nurture Nature” wanting to rent a full 10’x10’ custom green wall and logo as a backdrop for the guest speakers! Using a combination of indoor plants and wheat grass grown in between the Pangea logo, the backdrop maintained the attention of all the guests long after each speaker was done, and of course they walked right up to it and touched it in disbelief. The green wall gave the guests something to remember and in addition they will more than likely remember the sponsors commitment to being green. To infuse the attendee's memory even deeper with the message of cool green, a single cell Green Living™ Desk Top (a mini green wall specifically designed to accommodate a single plant) had been created with the sponsor's name and logo and given away as a parting gift.
Lexus and Pangea Organics' “Nurture Nature” organic, living parting gifts.
Pure Yoga in New York City; GLT rendition.
Pure Yoga, an Asian based company, has expanded into NYC with its first international location and is making a public statement by using the Green Living™ Wall system as its facade. Opening in June of 2008, the 1,000 square foot Green Living™ Wall was designed by plant artists, creating a mural of vegetation. Currently there are multiple blue chip corporations working on a green wall realizing it is a visual attractant. These are small but influential marketing examples of companies who are seeing the visual impacts of implementing green walls.
The aforementioned are green walls of marketing substance, so how does one embrace the green wall as part of their own lives? Let’s take it one step deeper, the "Green Walls as Art" term coined by Green Living™ Technologies, creates or better yet incorporates limited edition, one of kind pieces or the adaptation of the vegetation to complete an application that is outside the standard. The Green Wall as Art is not a square mural on a building facade. Rather, plant material combined with geometric shapes, a variety of material finishes, sizes, colors and even the perception of the green wall itself makes up the artistic venue.
MFO Park in Zurich, Switzerland
In fact, the inspiration of Green Walls as Art came as a combination of plants and the structural element inspired by the MFO Park in Zurich, Switzerland. The custom cable system allowed the plant material to resemble starbursts, intriguing and ironic that the park is used as a platform of multi media and artistic events such as a place to gather socially, concerts and art festivals - unbeknown that the park itself is art. This urban park raises form the ground as the vegetation reaches for the sky.
The work of Green Living™ Technologies sculptress Susan Rowley (Rochester, NY) has also included the aesthetics of green wall technology and custom sculptures. Pictured above is a limited edition green wall hand crafted from stainless steel. Each piece has a one of a kind finish since each one is done by hand. Also pictured is the work of Greenscreen’s columns and 3D curves. Combining geometrics and architectural design to the green wall will always provide visual impact.
Technology meets art: Left: NY sculptress Susan Rowley combining sleek stainless steel with soft plant material; Right: Look at this shape - imagine the possibilities! Source: Greenscreen
A leading designer of stunning visual green wall mural art is Patrick Blanc, who hails from France, and author of the soon to be released The Vertical Garden: From Nature to the City. His "vertical gardens" are renown for their scale, innovation and great variety of plant material, and he is the creator of Le Mur Végétal, a copyrighted system:
Musée du quai Branly vegetated "Vertical Garden" wall by Patrick Blanc in Paris, France;
Can we agree that the green wall is a form of art that attracts people to it like the sound of a waterfall? So then is the green wall the silent waterfall? Green walls are more then beauty, the added bonus is they are also functional. Go figure that they do more than look good, who would have known! Enough sarcasm, let's get serious for a second: did you know according to the American Farmland Trust the usable farmland in the U.S. is shrinking by 2.2 million acres per year (http://www.wvfarmlandprotection.org)? The changes in land use to our urban society have caused huge increases of runoff and flooding. The same changes are causing habitat destruction for flora and fauna and, of course, there are the common results of increased urban heat island effect, noise pollution, poor air quality, etc. This is not an excerpt to explain the effects of over-development but to stimulate thinking how green walls are also functional.
Let’s assume our society stops the clock on development. Using farmland, for example, we may not have enough to sustain the growing population, but be sure there are plenty of new developments with zero-land lots with plenty of vertical space. Who is to say we couldn’t utilize the green wall as crop production? Yes, we have seen grapes on trellises, but really how about growing peppers or tomatoes? Vertical growth is already happening across the globe on roofs in many cities like Toronto, New York, and Singapore, for example.
Changi General Hospital in Singapore. The Hydroponic microfarm on its atrium roof since 1988 feeds patients;
Green Living™ Technologies, Strawberry Establishment for Green Wall
And from our end, Green Living™ Walls are being manufactured in 4” (11cm) to 6” (15.25cm) depths to accommodate a variety of deeper rooted plant material and editable crops. The first commercialized walls (4) will be installed this summer (2008) in the Los Angeles California region in collaboration with www.urbanfarming.org and Cal Poly Tech to produce editable crops for homeless people. Green Living Technologies has partnered with Cal Poly to conduct further research to consist of storm water collection, heat absorption and acoustic values. The edible walls will contain a variety of crops that can be eaten raw to include: beans, tomatoes, peppers, leafy greens and strawberries. The lower cells of the wall will contain larger crops such as cucumbers, melons and eggplant supported by the ground itself while the roots thrive in the media within the green wall. In R&D look for dwarf blueberries and no-bog cranberries and let’s not forget vertical herb gardens!
Many butterfly feeding and breeding habitats have been destroyed by pesticides and urban development (http://www.projectwildlife.org). Butterflies are easy to attract; you just have to know what they like to eat. Caterpillars eat "larval" plants like milkweed, marigolds, Queen Anne’s lace, and violets. Butterflies like "nectar" plants, like the butterfly bush, the beauty bush, sunflowers, lilacs, snapdragons, and zinnias. So select plants that are diverse in color and bloom at different times, and you will attract butterflies all summer long. Using butterflies as an example, green walls can be planted to refurbish and repopulate natural areas that have been destroyed quite effortlessly.
Green Living™ Technologies
Poor indoor air quality (IAQ), also known as “Sick Building Syndrome,” can be many times worse than the air outside (www.epi.state.nc.us/epi/air). Pollutants can cause or contribute to short and long-term health problems, including asthma, respiratory tract infections, allergic reactions, headaches, congestion, eye and skin irritations, coughing, sneezing, fatigue, dizziness and nausea. Some facts:
• Indoor air pollutants can cause discomfort, and reduce attendance and productivity. Recent data suggest that poor IAQ can reduce a person's ability to perform specific mental tasks requiring concentration, calculation, or memory.
• Indoor air pollutants hasten building deterioration. For example, uncontrolled moisture can result in mold growth that leads to the structural decay of building components.
• Poor indoor air quality strains relationships among employees, family members, parents, teachers, students and school administrations.
• Indoor air quality problems can result in liability issues or lawsuits.
Green Living™ Technologies
According to NASA, the use of indoor plants has proven to remove such chemicals as Benzene, Formaldehyde and Trichloroethylene. My experience with this is that we have an indoor growing facility in the same area of manufacturing and although we haven’t done a formal study, it is true that the area with the plants is a much more comfortable area, supporting the psychological benefits argument to having indoor plants. Indoor plants are also supported by the U.S. Green Building Council. Numerous studies including those done by over 10 prominent researchers worldwide demonstrate that the ability of plants to metabolize Volatile Organic Compounds (VOCs) increases with extended exposure to VOCs.
The health effects of exposure to VOCs are consistent with Sick Building Syndrome effects, including eye/nose/skin irritation, headache, and lethargy. Several studies have also shown lower workplace stress, a decrease in fatigue and enhanced productivity by adding indoor plants to their interior environment. Two points are available in LEED - Office Interiors Indoor Environment Quality Credit IEQ-15 'Indoor Plants' to encourage and recognize the installation of indoor plants that improves indoor environment quality.
Green walls also improve exterior air quality. Air quality is directly linked to the urban heat island effect. Adding green walls results in a reduction in urban temperatures through the reintroduction of plants that would positively affect air quality by the reduction of smog days and air born particulates.
Green Living™ Tabletop w/ Basil
Remember that kid in the beginning of the article who was impressed by the bean plants? He is all grown up now with his own kids and refuses to let another bean plant die. Seriously, green walls can be introduced to the classroom. Instead of growing that little bean in a washed out milk carton we can now open up the minds of students from 1st grade to higher educational studies with opportunities to introduce data and newer technologies.
Without assuming, there may have been a notion of the same song and dance about the obvious benefits of green walls in comparison to green roofs such as the prevention of storm water runoff, curbing the heat island effect, monetary savings and doubling the life expectancy of the roof membrane, etc. And all are valid and key points. This article was to get you to think outside the box - who would have thought to use green walls as a major contributor of crop production and to replenish butterfly habitat? Well, we're not quite done, either. How about job creation? Green walls in all their beauty and function create green jobs through manufacturing, training, installation and maintenance contracts and so yes, the obvious theory in comparison to green roofs becomes more apparent.
Musée du quai Branly by Patrick Blanc in Paris, France;
Thanks for reading and it was my intention to get you to think about the many possibilities for green wall applications, how they are used and what some of the benefits are that we can implement now. For now, green walls provide a visual impact that cannot be denied and our feedback from clients say that since there are plants it must be “green,” when in fact the beauty is only as deep as the wall itself - what you don’t see is just as important.
George A. Irwin,
The Green Wall Editor
guest feature and inaugural column for The Green Wall Editor
An Intro to Green Walls and Green Roofs:
Living Architecture at its Best
By George Irwin, Industry CEO and President
All Photos Courtesy George Irwin unless otherwise
Green Walls Part I: Nomenclature
Since the days of Babylon, vegetation has been growing on, in or around both the horizontal and vertical planes of buildings, more specifically the roofs and walls. The most recent green trends have been including a variety of what the industry is calling “Green Walls, Living Walls, and Vegetated Façades,” and we have heard many more names, too. The green roof movement has naturally evolved to green walls - no pun intended, but the green roof has now climbed over the parapet and down, or up the walls.
Designers, architects and engineers now have the possibility of encasing a building in some type of live vegetation whether for aesthetics, function or notoriety. This article is the first in a multi part introduction to “Green Walls” that will define the nomenclature contributed by the leaders of green wall manufacturers, installers, designers and architects with support from Green Roofs for Healthy Cities (GRHC) and Green Walls 101© (GW 101).
Green roofs have multiple design and material components and so do green walls. Each project must be addressed with a variety of application possibilities, limitations, functionality and aesthetics. In order to understand the potential components relevant to specific applications we have to define the terminology of “Green Walls.”
The term “Green Wall” is a global term used to reference a variety of vegetated wall surfaces. Within the term “Green Wall” we have two specific categories: Green Façades and Living Walls.
• ‘Green Facade’ or facade greening, features a training structure that supports vines or climbing plants growing upward from the ground away from the building (GW101, 2008). Green Facades can now be dissected into two additional categories of product applications:
• A multidimensional, welded wire trellising system.
• A variety of stainless steel cable and mesh systems.
Both systems support a variety of climbing plant material, can be customized and some are available in a variety of colors.
Left: Welded Wire Trellising System,
Source: Greenscreen; Right: Cable and Mesh System, Source: Jakob
• ‘Living Wall’ is part of a building envelope system, comprising pre-vegetated or planted on-site panels containing plants, growing medium or liquid nutrient installed in or on a frame, secured to a structural wall or it can be free standing (GW101, 2008).
Living Walls can also be migrated into two distinct categories:
• Hydroponics wall which uses recirculation water to deliver nutrients directly to the roots of the plant material.
• Soil or growing media based walls. These walls are made up of a variety of modules that retain growth media to support plant material.
Recognizing the correct terminology is the start to deciding on a green wall system. Be warned not all systems are the same there are pros and cons to each system. Not all are “Do it yourself” applications, some perform only with a specific plant type or have a variety of mounting procedures and structural requirements...and more. For more information contact the manufacturer.
Green Walls Part II: The New Green Roof?
In case you don’t read the newspaper, watch the news, have internet access or any other media attention whatsoever, green roofs have proven themselves over and over again long term to be part of a Best Management Practice (BMP) in the fight of global warming. Long term data has proven that Green Roofs, when constructed correctly can:
• Retain and / or slow down a significant amount of stormwater runoff resulting in less erosion, reduced heavy metals in our water ways...etc…
• Double the life expectancy of a roof membrane
• Add acoustical value
• Regulate a building's internal temp
• Clean the air
And etcetera, etcetera, etcetera…
The Marketplace at Oviedo Crossing, Oviedo, FL; System:
There is one problem with the green roof and all its beauty and function...Unless it is yours and you have access to it, no one else can see the green roof (unless you are in an adjacent building).
Green Walls, on the other hand, can be a public display of beauty, art, expression and just as important as green roofs...functional. Green roofs have long term quantifiable data associated with them. Without boring you with statistical details, it can be theorized that a green wall will provide similar or associated benefits. Here is where the benefits may vary, depending upon the array of systems available; trellis systems, cable systems, growth media based systems, or a hydroponic system. With multiple systems come multiple benefits that may or may not carry from one to another.
A true correlation of green roof related benefits must be under a similar design. For example, the use of a 3” growing media based system should have a benefit correlation to a 3” depth green roof with similar vegetation properties. These same benefits cannot be expected with a trellis or cable system. However, the facades (trellis and cable system) can offer a multitude of other benefits not offered by a soil based system. This is part of the pros and cons mentioned in Part I. As a designer or architect it is up to you to decide on the system and its functionality. (Note: As a designer why not incorporate a multitude of systems in one project?)
The connection to the benefits will rely on the system, we can agree on that. Specifically speaking, what benefits do all the systems share? Cosmetics and aesthetics...fact is, when constructed correctly the green wall applications are very alluring and appealing. What do aesthetics do for me? As a non environmental benefit we used the example of the 2,000 square foot Green Living™ Wall for Anthropologies, a high end retail store in Alabama, and it attracted additional pedestrian traffic immediately to the store front - it can only be assumed that the increase in traffic equates to a rise in internal traffic / shoppers, increasing revenues for the retailer as a result of the extra attention, capturing those sales based on an interest in the green wall.
No matter what the system or plant material, there is a definite attraction to seeing a potpourri of plants cascading from the vertical heights of what would otherwise be an orthogonal boxlike structure. Some of the manufacturers have the ability to custom manufacture specific dimensions, create curvatures, and are now are incorporating green walls as art both indoors and out - green walls and green roofs as living architecture!
Left: MFO Park in Zurich, Switzerland; Right: National Wildlife Federation Headquarters in Reston, VA
Whether you are an interior decorator, architect, landscape architect or just simply interested, visit www.greenroofs.org for more information on attending "Green Walls 101 Introduction to Systems and Design" in a city near you. You can also visit Green Living™ Technologies in NYC on April 26-27, 2008 at the Go Green NY Expo and on April 29 – May 3rd in Baltimore, MD, at the 2008 Sixth Annual Greening Rooftops for Sustainable Communities Conference.
Be sure to visit Greenroofs.com again for additional Green Wall articles!
George A. Irwin,
The Green Wall Editor
Back to Top