Hurricanes, Wind Tunnel Testing, Florida Green Roofs and more

Extensive, non-irrigated green roofs for Florida and the southeastern US coastal areas.  Your MetroVerde Green Roof does not require irrigation, can survive long periods of drought, inundation, both freezing and sweltering temperatures while treating stormwater, providing wildlife habitat in the Urban Core and creating a beautiful Sense of Place.   Pictured above is the MV ER3 test panel at UF scheduled for wind testing in early 2010.  The test panel platform is adjustable from flat up to 45 degrees.  Because the system is a mat based structure - the roots are embedded into a monolithic, permanent platform - light weight - the MV ER3 weighs approximately 10 lbs per SF.

Plants for Green Roofs in Florida

Wow. I drove to Tampa from Jacksonville this week and witnessed first hand the damage last week's twenty degree F temperatures did to horticulture across the state. We must all remember that even south central Florida may be subject to hard periods of cold, freezes and frosts.

Balance. The word that kept popping up in my mind was 'BALANCE'. In designing a green roof for Florida we must keep in mind the 5 H's (they have grown to five from my initial three) - Hurricanes, Heat, Humidity, Heavy Winds and Hard Frosts.

Choose your planting scheme to include three components!

Number One - use the standard green roof plants that survive no matter what. These include plants that come through hard freezes and boiler-type humidity periods. There aren't many of these but there are a few...

Number Two - Select some of the Sedums that will thrive in the winter. They will limp through the summer though. Their poor summer performance can be offset by Number 3.

Number Three - Select those plants that thrive in the summer monsoons but limp through the winter.

A good green roof plant designer will be able to deliver year-round color and interest.

Remember - we focus on non-irrigated Extensive Green Roofs. Roofs that are light weight - no more than a couple two or three inches think.

Florida is tough on Green Roof plants.

Hands on experience through many years or trials is what will produce the best design for each Florida location.

Happy Green Roofing!

Kevin

Propagating Green Roof Plants for Florida Green Roofs

Propagating plants for green roof projects here in Florida is an important component of a successful Florida GR project.

Knowing a plant was raised in the same ecotone where it will ultimately be used is important. This not only secures LEED credits for local material use (and other credits) but it helps in knowing the plant can survive local climatic conditions.

My general rule of thumb is that, here in Florida, a green roof plant should be grown no greater than 150 miles north or south f the project physical location - no general limit on east/west other than the local limits for LEED credit.

The roots shown on the succulent leaf here developed on their own, on a leaf dropped as mother plants were being pruned, a testament to the hardiness of plants. The above pictures also show the importance of saving pruned plant material for propagation - and in doing so being a good steward of resources.

Happy Green Roofing!

Succulents for Green Roofs and more Sunday Night musings...

The blog data here is a continuation of my previous Green Roof blog. Feel free to refer back to the site to my new Green Roof blog because it does contain alot of information - and I will be posting the same info both here and on the Green Roof for Florida blog for some time.

We use succulents in most all of our green roofs. Succulents are an excellent green roof plant in many different ways. Succulents generally store water in their stems and leaves in significant quantities. Cacti leaves are practically non-existent and most photosynthetic functions in cacti occur in the stems. Succulents have stomata on all green surfaces but at much lower surface densities than most other plants.

Because succulents store water they can survive and in most cases still 'look good' after a significant drought. Another benefit to succulents is one of offering a deterrent to fire through their water filled leaves and stems.

Some other drought tolerant non-succulents such as the sages and grasses produce flammable volatile oils that can add fuel or accelerant to a fire.

Most succulents do not need fertilizer in quantities required by non-succulents. We have seen the base nitrogen content in rain provide sufficient nutrients for many green roof succulents.

Succulents also do well in well-drained soils that will wick and absorb a minimum amount of water.

Today engineered soils, such as the MetroVerde engineered soil blends have taken the place of most 'dirt' on the roof.

And finally, we are now prepared to say in our opinion, the green roof plants we propagate and raise like round rays and pots better than square ones.

After viewing first hand the growth qualities and characteristics of our green roof plants grown from seed in round and square containers, and cuttings in both, we believe the round container has less negative impact on root formation than the square shape.

Although there is not a huge significant difference, we've noticed a definite difference in size and in transplanting issues.

Unfortunately round pots are not as space efficient as square pots.

Has anyone out there seen studies conducted on the difference between square pots and round pots? I'd like to hear from them.

Happy green roofing!

Green Roof Planting Media - Second and Third Generation Products

After literally thousands of soil mixture experiments we are making strong headway in developing the green roof soil medium that has the qualities we are looking for. As we look back over the years we can readily see how far we have come.

We've addressed the drainage and the flammability and the dust and the compactability and the water retention and the nutrients/organics issues.

Erosion was a huge issue that we wanted to resolve. Our focus was on lightweight, thin (low profile - primarily because of Florida's hurricane propensity), inexpensive vegetated roofs that would not only work on flat roofs AND we wanted our roofs to work on slopes - even severe slopes!

Today I installed a 20SF vegetated panel on a vertical wall at the house, less than ten minutes after the engineered soil and plants had been applied. Wow. We have come a long ways.

But we have a long ways to go.

Now that flexible vertical vegetated panels - less than 1" thick are a reality - now we are looking at technology that will allow us to apply vegetated panels directly overhead on ceilings. So here is the next challenge.

The era of filling planters or trays with dirt, loose soil mixtures, LECA or expanded clay and placing them on the roof is disappearing. Like the dinosaurs these applications will hang around for a while, with good usefullnes with large heftily
-engineered structures. LECA and Expanded Clay may soon be against building code in Florida for use on roofs - imagine a truck bed load of LECA pellets fling through the air in 150 MPH winds - something like a shotgun blast.

Toxicity free engineered planting media will be a requirement. LC 50 testing with minnows will become standard. Green building requirements will affect planting media design too.

The challenges are here - so are the opportunities...

Happy Green Roofing! Kevin

Green Roofs can be vertical green vines also - Choosing the right plant and planting system lays the foundation for success.

Try a MetroVerde Shade Trellis! Based on the concept that a deciduous vine will block solar gain during the summer when the leaves are growing and allowing needed heat during the winter months when the leaves are off - MetroVerde's shade trellis combines plant requirements with awning frame design to produce a product that 1. cleans stormwater, 2. provides habitat and 3. creates a beautiful sense of place!

Check out this Website - Living Houses! Living Group Designs and Plans Review by Karl Wilson

Wow! Karl Wilson revealed a set of Green Parking Garage plans and I met two green architects - Alain Dezii and John Szerdi this week. Their Architectural firm in Fort Worth is a living building - all the gray water is treated in modular interior wetlands and the only potable water is used in the faucets.

The open air plenum system keeps the 4 story building amazingly cool!

They even have roof gardens - with native grasses, palms and more!

Think of Alain and John when you need a green, living building design! Check out their website!

Think of Karl's solar panel shaded parking garage roof with living walls when you think institutional, medical or parking garages! Check out Karl's website!