Trashy breakfast – Please recycle!

Dear Hampton Inns:

I enjoy staying at your hotels and I especially enjoy getting up and eating breakfast. I’m ALWAYS disappointed , however, in the amount of trash that I generate at breakfast, especially the foam materials that do not degrade in our overflowing landfills. At the very least, I hope you will consider using recyclable products and recycling them. My family of 5 can generate a whole bag of trash at one sitting!

Love your coffee but try to remember to bring my own cup,

Connie Roy-Fisher

My husband is a Hampton Inn fan. On our trip to Athens to teach at the Art and Science of Healing Gardens Symposium, we stayed at, of course, Hampton Inn. If you have eaten breakfast at Hampton Inn, I hope you have noticed the amount of trash that you generate – EVERYTHING is packaged in plastic, they use foam plates, bowls and cups, plastic silverware and cups. NOTHING is recycled. I’m sending this letter. Please feel free to copy it and send it as well.

Should we Share?

This spring I had an intern from Florida Atlantic University that is excited about everything green. South Florida geography makes the LEED point requiring that materials be within a 500 mile radius challenging. Furthermore, many products indicate that they use recycled materials but do they meet LEED requirements regarding percentages and post vs. pre consumer waste? My dream has been to put together a list of materials that meet these requirements for South Florida. The materials I’m interested in as a Landscape Architect would be concrete, pavers, wood, irrigation equipment, light fixtures, outdoor furniture, metals, sealers and preservatives.

The intern took the project on and began researching on the web. She found a million products that claimed to be green. In order to focus her efforts, she contacted “green” consultants to see if they might have some sort of list from which she could start. These businesses wouldn’t help; she felt that they were unwilling to share.

I guess there could be a couple of reasons for this. The most obvious reason to a business person would be that they are getting paid for this service. Through the intern’s eyes, shouldn’t we be sharing this information for the better good? Couldn’t the ‘green ‘consultants get a percentage from the products they include on their list? Or – maybe these lists don’t exist at all.

What do you think? Are those lists out there? Should the information be shared?

RIVER OF GRASS CANOE/KAYAK EXPEDITION

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RIVER OF GRASS CANOE/KAYAK EXPEDITION

January 2-7th, 2010

Celebrating the Everglades Coalition's 25 Years of Activism

ARE YOU A HARDY SOUL, IN FIT CONDITION, AND AN EXPERIENCED PADDLER??

DO YOU LOVE OUR EVERGLADES??

ARE YOU A SCIENTIST? ARTIST? TEACHER? JOURNALIST? SPORTSPERSON? HEALTH PROFESSIONAL? PUBLIC SAFETY PROFESSIONAL?

If you qualify in the first two categories and at least one of the professional categories in the third--the RIVER OF GRASS CANOE/KAYAK EXPEDITION January 2-7th, 2010 may be for you!!

This bold venture marks the 25th year of the Everglades Coalition's annual conference, and launches West Palm Beach's Year of the Everglades. West Palm is the host city this year for the Coalition's big event.

The 77 mile route begins at the point where the Kissimmee River flows into Lake Okeechobee, travels around the NE rim of the lake and South to the point where the L-8 Canal leaves the lake at Sand Cut, travels down the L-8 Canal to the junction with the M Canal, and then travels the M Canal to the Visitors Center at Grassy Waters where the expedition will be met by the 2010 Everglades Coalition Conference delegates on January 7, 2010.

The last leg, into Grassy Waters, is especially significant to the City of West Palm because it traces the city's water supply source from The Everglades flow system. There will be a Grand Finale Flotilla on this last leg, where all who wish to join in the paddling procession into Grassy Waters on January 7, 2010 are encouraged to join. More information on how to participate in the Grand Finale Flotilla will be available later.

For additional information, please EMAIL:

Joan Sterrenberg sterrenb@indiana.edu

To apply for the entire 77 mile, 5 day canoe expedition, scroll down to the application,print it out and send it by July 1, 2009 to:

Email to: PlantCypress@aol.com

Mail to: Arthur R. Marshall Foundation

2806 So. Dixie Hwy.

West Palm Beach, FL 33405

________________________________________________
Grassy Waters Canoe/Kayak Expedition

January 2-7, 2010

Application

Name:

Address:


Email:

Cell Phone:
Home/Office Phone:


Education:


Professional Affiliation(s):



Age: Gender:


List Any Health Issues:


Area(s) of Expertise: (Science, Education, Media, Arts, Recreation, Health & Safety)



Canoe/Kayak Experience:




Availability: January 2-7, 2010
If not available for the entire time, please specify dates you are.



Return Application by July 1, 2009:

Email questions to: Joan Sterrenburg - sterrenb@indiana.edu

LEED and Landscape Architects

I’ve been a LEED ap for three years now. Although I do a number of government projects and I’m active in USGBC, I have not done a LEED project yet. Why?

Part of it is that South Florida is way behind the rest of the country in LEED projects. The economy may have something to do with it as well.

Unfortunately, I’ve seen LEED projects for which a Landscape Architect was chosen that was not a LEED ap. It was apparent in the finished product that they were not familiar with what LEED was trying to accomplish. Why were they chosen for the project?

To me, the site and what happens on it are critical but it is often an afterthought to architects and civil engineers that are the project managers on these projects. Maybe they think anything that is planted is “green”. Maybe we, as Landscape Architects don’t care enough to learn about sustainable ways to do things successfully. Maybe we haven’t done a good job of educating project managers, explaining the benefits of our services enough.

Saving the earth should start with exactly that – making sure that we don’t compact the earth, we maintain or improve the quality of soil, we save or restore vegetation that cools temperatures and reduces carbon and we collect, preserve and clean water just to name a few. SPROUT!

Green Roof Update – Bulbine is the Bomb!

My apologies, I haven’t kept up my updates on our test strips. I also have not been able to add to our test strips as we had originally planned. It’s been a busy spring – putting together presentations and teaching on green roofs, evidence based design and healing gardens as well as working on the West Palm Beach Waterfront project.

Probably the most important thing we’ve learned is – put in an irrigation system with a moisture detector. Despite our best intentions to stay on top of rain events and water after 10 days of no rain the strips went through periods of neglect. Fortunately we have had a lot of rain the last couple of months, so I got brave and went up to see how things were doing.

In the 4 inch media depth everything was still alive. The bulbine actually looks great. The mimosa and perennial peanut are still there but struggling.

In the 8 inch media the equisetum had died and devils walking stick had taken over. Devil’s walking stick is usually considered a weed but is actually a great bee and butterfly plant so I’m leaving it. The grasses are hanging in there.

Sources for Sustainable Landscaping

Check out this months issue of Neighborhood Gardener. (link to your right) It's a great source of information on sustainable landscaping. This issue has an article on Florida Friendly landscaping with links to a plethora of information and an article on the latest irrigation controllers being tested by University of Florida.

Local Master Gardeners Program and Florida Yards and Neighborhoods, both run by IFAS (Institute of Food and Agricultural Sciences) at the University of Florida educate South Florida residents in sustainable planting, maintenance and water preservation principles. To learn more, call the Extension Service at the Mounts Building in West Palm Beach, 561 233-1759.

Editorial

by Jake Fisher, Roy-Fisher Associates

Weinstein, Neil & Kloss, Christopher. The Implications of Section 438 for the Green Technology. Stormwater, March/April, pg 8.

In a recent editorial in Stormwater, experts Neil Weinstein and Christopher Kloss discussed the likely impact of Section 438 of the Energy Independence and Security Act. Weinstein and Kloss declare Section 438 requires federal facilities to meet predevelopment hydrology for new building construction over 5,000 square feet using planning and nonstructural and structural best management practices (BMPs) to the maximum extent technically feasible. The underlying goal is to protect and restore watersheds using technologies that make sense for the site and the targeted management goal thereby promoting the use and development of the most efficient technologies. Currently being produced (via an EPA Subcontract) is a guidance document which will create the framework for innovation and research needed to develop this high-performance approach.

Furthermore Weinstein and Kloss maintain Section 438’s representation of an “important next step toward improving the health of the nation’s waters and signifies Congress’ recognition of the work of the EPA and its partners advocating for greener stormwater controls.” Section 438 will bring increased green infrastructure at federal facilities. For example, vegetation will be used to intercept rainfall and evapotranspirate moisture back into the atmosphere, undisturbed or enhanced soils will allow natural infiltration, and water harvesting systems will collect and reuse rainfall on site. Green infrastructure, effective at reducing the volume, peak flow, and pollutant load of stormwater will be used to reduce the burden on existing infrastructure and to protect receiving streams. The new law allows the federal government to become the earliest innovators within the realm of sustainable infrastructure which can be used to provide numerous positive outcomes for the environment (and in so doing develop the federal government’s “economic and environmental sustainability”.

Weinstein and Kloss additionally assert the interconnectivity of water and energy stating “the transport, use, and disposal of water are energy intensive” and “integrated water management that recognizes the resource value of water will lead to improved energy efficiencies and conservation”.

“The federal government is the largest landholder in the US; the passage of the EISA, coupled with a renewed commitment to infrastructure investment, presents a unique opportunity to establish an improved infrastructure network”.

Glenn Acomb & UF Green Roof

Although your test plots are useful for general observations, I would caution you that they do not replicate green roof conditions very well.

Testing with container as small as these will yield results from which you cannot easily base conclusions.  The ambient temperature of a roof is a combination of the heat generated by direct and indirect means as well as the insulation provided by the plants and media.  The typical high temperature range for a Florida conventional roof is approximately 140+ degrees F, versus the high for a green roof at approximately 80 degrees F (UCF, Dr. Marty Wanielista, 6" planting media + 2" drainage media).  We have found our temperatures to be similar.

Your test plots will generate heat that is greater than normal and this will cause plants greater stress and lead you to believe that these conditions are typical of a green roof.  the heat will also distort the water balance by excessive drought and cause you to believe that you should irrigate more than you would in a green roof of a larger area.  The mortality you experienced is likely due to the heat and perhaps, drought. 

As I talk to many professionals that want to know my experience with the UF Green Roof, I find myself explaining that a green roof should not be seen too simplistically.  It is not as many believe, a mere planting of plants on a roof.  There is much more to consider.  It is an environment hotter and drier than a terrestrial landscape.  The media performs differently.  One must know much more about plants (growth rate, root depth, capacity to retain water, and more) as well as the water cycle/delivery and irrigation system for plant processing.

Your blog comments about plants and their appropriateness for certain media depths.  Please be careful with conclusions based from limited tests.  For example, I would NOT recommend Muhly Grass for even a 6" media depth.  It has not done well on the UF green roof, which is a 5" depth.  I would suggest at least 8" or 10" for a healthy plant.  If one wants to know for sure, pull up mature plants (from a similar soil and environmental condition) and measure their root system.  A depth of 4"-6" is not very much for most plants.  Further, with depths that shallow, the choices do not include many ornamental-like natives. 

In addition to the characteristic of media depth is another important issue of the media itself.  Most green roof product mixes are very well-drained shale-based (or similar type of well-drained soil) and the infiltration rates are much greater than soils in which we are accustomed for use in conventional terrestrial landscapes.  Infiltration is rapid and residual saturation is brief. 

I would recommend that you increase the plot size as large as you can to correctly base conclusions.  I am working on a paper that summarizes my experiences of the past year with the UF Perry Construction Yard Green Roof and it will summarize this and the plant material responses in a North Central Florida environment.  Many, but not all of the plants will easily adapt to a South Florida application. 

Glenn A. Acomb, ASLA

University of Florida
Department of Landscape Architecture and
The Program for Resource Efficient Communities

Attracting Wildlife

We are going to start a series of monthly green tip posts. These tips will reflect on a new way to help infuse your garden and life with green living!

Green Tip #1:

Attract Wildlife to your Garden

                                      Photo: Award winning Jacqueline Fiske Healing Garden                Photo Credit: Michiko Kurisu

Florida has a diverse wildlife population, but rapid growth throughout Florida is destroying native wildlife habitat. But, make some basic changes to your landscaping and you can create a yard that will provide habitat for a variety of birds, butterflies and beneficial insects.

• Increasing the variety of plants in your landscape design.
• Creating natural corridors with bordering properties to allow wildlife to move through the larger neighborhood.
• The easiest way to attract birds, butterflies and beneficial insects is to select and plant flowers, shrubs and trees that bear fruit, seeds or flowers that birds and other wildlife depend on for food.
• A birdbath, fountain or pond is an important source of fresh water that will attract birds. Constructed ponds provide important water resources for a variety of wildlife.
• Avoid using pesticides and other chemicals on a regular basis without reason. When necessary, choose the least toxic controls to minimize harm to birds, butterflies and beneficial insects in your landscape.

Source: www.Floridayards.org

Florida Green Lodge

I was disappointed when I picked up a flier on the requirements to be a Florida Green Lodge and noticed that there were NO site or landscape considerations. While it is very admirable that hotels are beginning to conserve water by their laundry practices and low flow plumbing fixtures, shouldn’t there be a requirement to conserve water in the landscape?

There are admirable energy efficiency requirements but these could be supplemented with additional requirements for low energy outdoor light fixtures and planting appropriate trees to shade buildings and air conditioning units.

Additional best management practices should include plant selections and planting methods to reduce fertilizer and chemical runoff, full cut off outdoor lights to protect the night sky, sound stormwater retention practices and areas for wild life habitat.

Plant Decline Follow up

We pulled out a portion of the perennial peanut that died back. The dead plant is on the bottom of the picture and the roots are on the top. There were still some live roots. It did seem a bit fishy that the cold snap would hurt the perennial peanut since it grows far north of here and this was confirmed by Patti Veale at Sunset Specialty Ground Covers. There were still some viable roots (white stringy things) On inspection a few weeks later, there had been some recovery on the remaining perennial peanut which points to drying out and not freezing as the cause of decline.

Lesson learned (again) - a moisture sensor/automatic way to irrigate is important to green roofs in South Florida. Just like the Key West Brown Roof, if you don't stay on top of the water, the plants don't make it. Fortunately, we discovered it before we totally lost the perennial peanut.

Many green roof installations may be on buildings where there is not easy access or interested maintenance personnel. It is so important that there be sensible but automatic watering as well as regularly scheduled maintenance checks. One of our next steps will be to research easy to use, reasonably priced moisture sensors so that we can report on how to incorporate them into they system.

Second Test Strip Launched

We finally have the second test strip on the roof.

(Planted November 7)

This strip has deeper media (8”), and is planted with a Muhly Grass, Cordgrass and Equisetum, all native plants. We chose these plants because they are native and can take both drought and inundation in water. According to other studies that we’ve looked at, you need at least 6” of planting media for grasses. The Key West green roof only had 4” of media and this may have been part of the problem (See Key West Brown Roof). My hypothesis is that the grasses will do well but that the strip will become root bound quickly in the 15” x 30” planter, and that larger planting areas are required for grasses. We’ll report on this strip monthly with the original strip.

Death on the Roof

Not a happy report this month. The perennial peanut has passed away and the mimosa strigulosa took a dive but appears to be coming back. The bulbine looks a little stunted but has several blooms.
Why did the perennial peanut and mimosa perish? What could have caused so much damage after not only surviving, but thriving through two months of brutal heat? There was plenty of rain so it couldn’t have been drought. We checked to make sure that the drainage was working and it is, so they didn’t drown. The perennial peanut is supposed to fix its own nitrogen so it couldn’t have been a nutritional deficiency. There are two possible problems that I can determine. Please write in if you think it is or isn’t one of these factors.
Even though both perennial peanut and mimosa strigulosa live in cooler areas than here, we had a record low in October. Unfortunately, we didn’t check the temperature on the roof, but the ground temperature was in the 40’s. While both plants should have survived 40 degrees, maybe the planting media (lava rock and peat) is unable to hold any heat and the low temperatures were cold enough to damage the plants. The perennial peanut and the mimosa were planted on the ends of the strip so it may have been colder than the middle location where the bulbine is.
The only other possible causes that I can think of could have to do with the test strip construction (the sides ended being slanted as the pond liner shrunk a bit, or, there could be some type of nutritional dysfunction because of the planting media we picked.
This leads to a thousand other test strips that we would like and should try, if only we had time and money. Any leads on grants? Testing different planting media, planting media depths, and more plants, especially native ones, would help to ensure that we could reap the many benefits of green roofs in South Florida.

Willow Queen

My husband now calls me the Willow Queen. I guess it could be worse. I have been wandering muddy areas around Jupiter getting willow cuttings. It started with a park we are working on with Glatting Jackson in Boynton Beach. We wanted to provide sensory experiences with plants and came up with willow tunnels as a good way to provide green play things. Of course, it hasn’t been done in South Florida. All of the information we could find on the web came from England. You can actually order live kits for a variety of willow constructions. Unfortunately, the willows that live in England do not live in South Florida.

While there are probably a large number of plants that would work, coastal willow is native to South Florida and we decided to try it. Unfortunately, local nurseries don’t grow many Coastal willows; we could only find two trees in our area.

The RFA team planted the two store bought willows 5’ apart at Terracon Services out in Jupiter Farms. (picture above) These willows can become stock and will also allow us to at least tie together and braid some taller established willows. We also grouped some cuttings we made in groups of three and planted them in three gallon pots in the garden area behind our office. They rooted quickly and easily and we hope to plant them somewhere close by so that we can keep an eye on them as they grow and start the braiding process when they get to be about 4-5 feet tall. We’ll post quarterly pictures once they are planted in the ground.

Sprouted willows ready for transplant.

Test Strip Update

The test strip thrived for its second month. The beginning of the month was very hot,(up to 120 +degrees) and we had 10 days without rain, so we turned on the drip irrigation once. After that, we had several inches of rain and the plants, as you can see, are thriving. This is a picture from October 9, 2008; we are a little late in posting the September report! The next report/picture will be taken the first week of November. (the strip was originally planted August 8)

Green Roof Rx

My interest in green roofs began because I design gardens at Healthcare Facilities. There is a rapidly growing movement called Evidence Based Design that researches, applies and educates designers,healthcare administrators and their staff on the effects of the physical environment as a component that can improve health outcomes. (Ulrich, Zimring, Joseph, Quan, Choudhary 2004) In studies done by Roger Ulrich in 1984 one of the evidence based design principles that reduced the length of hospital stays, blood pressure, requests for pain medication and complaints of gall bladder patients was exposure to nature and positive distractions.

As part of my ongoing research at healthcare facilities, I tour patient rooms and views whenever I get a chance. What do most patients see? A large number of patients spend all day in bed looking at ugly roofs and air conditioning units. Wouldn't it be great if they could look out the window and see plants and flowers in a green roof planting instead?

It has been hard enough over the years to build my practice in healing gardens on the ground floor. The medical profession often looks at things in black and white, because they continuously have to make life and death decisions. Trees and flowers, though proven to improve health outcomes, seem less important than expensive machines and pharmaceuticals. Convincing hospital administrators to try a construction/planting method like green roofs that is largely untried in South Florida will not be an easy sell when they have so many other things to worry about.

It is so important that we get green roofs going in South Florida so that hospital administrators, government officials and commercial ventures can all take advantage of the many benefits green roofs offer. By testing materials and constructing demonstration green roofs we can determine the best design practices for South Florida and educate the public on their benefits.

Sprout!

First Month on the Roof

The first test strip is a month old! The month of August was gentler than usual in South Florida, many days were around 70, with a few scorchers on the roof at 120 degrees. We had over 12" of rain. Not a bad month for a test strip and it is thriving. The drip system is in place for use during drought periods.

Jurisdictional Agencies Meet to Consider Credits for Sustainable Stormwater Management

South Florida Water Management and DEP are among jurisdictional agencies meeting in Orlando today to develop new laws regarding sustainable solutions for storm water management including practices encouraged by Low Impact Development. Low Impact Development includes stormwater and land development strategies that emphasize conservation and use of on-site natural features integrated with, small scale hydrologic controls in an effort to mimic predevelopment hydrologic conditions. Practices include minimizing impervious area and compaction, rainwater harvesting, permeable surfaces, depression storage, bio retention, soil filtration, vegetated swales, enhanced stormwater ponds and green roofs. Retain, Detain, Recharge, Filter and Use!

Project Test Strips

On August 8th we planted the first of what we hope will be a series of test strips experimenting with different recipes to determine the best plants, planting media, planting methods and maintenance activities for green roofs in South Florida.

We are not testing the layering system, waterproofing etc. We are using the easiest construction methods and least expensive materials for the trays and layering system because of budget constraints. The trays are made of pressure treated pine. (cost not weight consideration) The tray is lined with pond liner. A layer of “cups” approximately 2" deep are laid out on the pond liner to mimic commercial drainage systems that get water out of the planting media yet store it for future use. We made this layer out of recycled soda cups. This layer is protected by a filter fabric. The planting media goes on top of this.

The layering system loosely resembles what has been developed by others, commercial green roof providers and the system designed by John Szerdi at the Eco-Centre in Lake Worth.

We are planning to start with two test strips and would like to add more as time and money allow. Only one has been installed so far.

These are the parameters of the test:

Two trays 30” x 30”

One tray will have a 3” planting media depth.

One tray will have an 8” planting media depth

We will plant a mixture of plants in both trays

The 3” tray will have spreading ground covers: Bulbine, Mimosa Strigulosa, Perennial Peanut

The 8” tray will have a mixture of grasses: Wiregrass, Equisetum, Muhlie Grass

Some wildflower seeds will be mixed in with the grasses, just to see what happens: Greeneyes, Gallardia, Coreopsis. These were recommended by the Florida Wildflower Coop.

Both trays will have the same planting media:

50% black lava rock mixed with 50% Canadian peat topped with 1” shredded eucalyptus mulch.

We will ensure that the strips get water, at a minimum, once every three days through an establishment period of one month. After that month, the strips will only be watered if there is less than 1” of rain over a period of 10 days.

We will take pictures of the plants once a month and post them on the blog.

After three years, we will pull the plants to examine their root mass.

These are our assumptions:

Soil mix: We wanted to develop a mix that would be light, drain well and have a little bit of organic material. The lighter colored mulch on top will keep the planting media cooler and retail some water. The black lava rock will have a better ph than red lava rock.

Plant choices were made from our experiences with plants in South Florida. We wanted to use plants that could take very wet or dry conditions in case the tray became flooded over a period of South Florida rainy days. We feel that a mixture of plants is better than a mono culture. Our plant selections are not all native but are selected because we have found that they are very tough and adapt to wet or dry conditions.

We used “trays” for several reasons. We did not have a location to do a full out extensive green roof directly on the roof membrane. Many people feel that trays won’t work in South Florida because they’ll blow off in a hurricane. There are two ways that wind can be approached. The first is to make the “planters” weighty enough to resist hurricane force winds as John Szerdi did at the Eco-Centre. The second is to secure lighter trays to the roof securely enough to resist uplift. We developed one detail for this with Botkins and Parssi for a penthouse garden in Palm Beach and have some alternative attachments that we would like to test in the future. For this project we plan just to put the tray on the roof and remove them when necessary.

Another reason I wanted to experiment with trays is because I’m concerned about what will happen when plant roots make an extensive roof “root bound” over a period of time. Since plants don’t go dormant in South Florida, will the roots take over within 5-10 years? Would the whole roof have to be replanted over a period of time? Or would it be easier to switch trays out? Or, are there plants that wouldn’t develop much of a root system and still survive?

This is our hypothesis:

The plants we have picked are survivors.

After three years, the roots the tray will be ‘root bound’ to a point that it would jeopardize plant health in the following year. The implication of this would be that it would be best to use trays that can be switched out or a plan to replant the roof after 3-4 years.

Potential future test strips:

Dune plants – will they be able to take inundation of several rainy days?

Lighter colored lava rock no mulch – determine weight savings, does ph matter?

Mono cultures (all one type of plant)

Parallel trays that aren’t disassembled after 3 years to see how much longer the plants survive.

Do you have any other ideas?

Please let us know what you think of our assumptions and the way we have set the test up.

Sprout!

Don't Call it Dirt!

If you go to one of the excellent classes provided by Green Roof for Healthy Cities, a point that is emphasized is that green roof plants are planted in planting media and not soil or dirt. Why? Most green roof applications are concerned about water retention and weight. Organic matter has a tendency to hold onto water and weigh more, depending on its actual composition. Therefore it is of greatest importance that the planting media is carefully thought out, specified and installed.

The factors that affect media selection are climate, weight, fertility, depth, location, microclimate and irrigation or lack of it.

The products used are typically a mixture of organic and inorganic matter with significantly more inorganic matter in extensive systems. Inorganic matter used includes vermiculite, expanded slate, expanded clay, lava rock, coarse sands, pumice stone, zeolite, diatomaceous earth, perlite and rock wool.

Planting media is critical to long term plant survival, stormwater retention and heat mass transfer. The composition of the media determines the system’s saturated weight, evaporation, drainage capacity and compactability. Plants need water, air and space for roots and nutrients. How well these needs are addressed depends on the planting media.

An area of controversy within the industry is how much organic vs. inorganic material should be in the planting media. The Winter 2008 Issue of Living Architecture Monitor addressed this issue. The inorganic supporter, Chuck Friedrich defines planting media as the particulate matter or substrate that anchors plant roots to sustain plant growth. His recommended mix is:

1. a lightweight aggregate, 3/8” or finer to provide space to retain water and nutrients. The lightweight aggregate will lighten the load and be permanent.
2. Quality sand to provide a filler and stability
3. Organic compost for microbial activity. He points out that currently there are no standards for organic compost.

He gives the following plugs for inorganic planting media:

Inorganic materials provide good drainage

Inorganic materials do not change over time like organic matter does. Organic matter can break down and wash away. Replacement of organic material can be labor intensive. Organic material may produce fine particles which clog filter fabric.

Inorganic media ensures that enough air can be provided to encourage roots to go down instead of up because of oversaturation. If roots are down, the plant can sustain itself during periods of extreme temperature.

He instructs NOT to mix fertilizer into the planting media but to apply it directly to the plants after planting. He also recommends the availability of irrigation for droughts.

The Organic supporter, Rick Buist, bases his support for organic media on over 80 successful installations using organic based planting medias. He feels that the push for non organic planting media stems from proprietary blends. However, the “Organic based planting medias” used in the 80 successful installations are not defined, so it is difficult to tell the degree of difference between Rick and Chuck’s arguments.

Many current practices regarding planting media rely on a set of standards developed by a not for profit group in Germany, Forschungsgesellschaft Landschaftsenwicklung Landsschaftsbau. It seems that there is also confusion regarding what organic material is and how to measure it from Rick’s review of the FLL standards. Differences can occur if one considers the standards for mass or volume of organic material. Furthermore, the standard focuses on material specifications rather than performance specifications, which doesn’t allow room for specific applications or creative solutions.

Chuck does make some good points for organics in the following excerpts:

“The performance which organic matter brings to stormwater retention, pollutant degradation, plant variety, cooling benefits, sustainable materials, etc. is too great to ignore.

“Organic-based growing media can hold far more water than mineral based growing mediums while maintaining porosity: this is because of the way in which they hold water through particles swelling instead of just void filling and capillary forces. Biology can be customized to degrade specific and non-specific pollutants. Plants that provide evaporative cooling can be used more frequently with success. Fertilization can occur naturally through nutrient cycling. Materials can be sourced locally.”

“Practically every argument I have heard against the use of organics comes with a relatively easy solution:

Lost depth because of organic cycling is easily addressed through inputs such as biomass created by the plant choice through roots or refuse or annual (if required at all) top-dressing with a pelletized product such as compost or alfalfa (readily available in a dry, bagged form)

Fines clogging drains or water logging can be averted by careful selection of organic materials. Organics with crystalline structures such as certain bark-based products will behave much like sand for free drainage while organics with strand characteristics will hold structure together. Careful selection and installation of components such as filter cloth are also helpful.

Wind erosion is averted by using biodegradable netting until plants are established, thereby providing continuous cover.

Fire prevention can be improved by avoiding certain substances (i.e. peat moss – a limited resource) and by using organics with a high ignition-thresholds and large moisture-retention capacities. Although any biomass on a roof can burn, it is easy to mitigate the risk by paying attention to the details.”

Source: The Organic Question, Living Architecture Monitor, Winter 2008 Volume 10, No.1.

How can we apply these observations into a planting mix? Please share any thoughts, recommendations or experiences.