How Hot Do Green Roof Plants Get? Green Roof Plants For Florida and the Southeast

We are seeing 150 degree F leaf surface temperatures this week in Jacksonville.  You need a plant with a low leaf stomata to leaf surface area ration to survive these temperatures.

Irrigation and Green Roofs, Green Roof Plants and Summer Heat

Green Roof Temperature Data

Summer is here and it is hot on the roofs!  Check out the data below we collected this week.

 Using an Extech IR Thermometer AN200 we measured the surface temperatures for portions of the Florida Green Roof, surface temperatures on plants growing in the adjacent ground and then surface temperatures of non-vegetated roofs.  Readings are an average of July 26th, 27th and 28th taken hourly.  Several items stand out.  The green roof agave leaf surface temperature reached 149 degrees F.  That is alot of heat to subject a plant to.  There was significant difference between the decking below a green roof and the decking below an asphalt shingle roof.  The flower on the hibicus growing in the ground, though a brighter color was generally cooler than the leaf on the same plant.  We are collecting additional data and will be publishing our conclusions in the next couple days.  For more information call Kevin 904-294-2656.

Amazing Green Roof Plants - Plants For Florida Green Roofs

It is the time of year where the sedums and other succulents really suffer here in Florida.  It is concerning to have watched the sedums flourish through the winter drought and cool spring then develop rot.  Unfortunately the daily high humidity found in Florida at this time of the year creates serious pressure cooker like situations on a roof - steam - heat - water.  Most succulents will not survive the summer humidity, and in fact if there are too many on a roof, they will create an area that breeds deseases that can affect other green roof plants.

The moral of the story here is to use a blend of plants - the picture here is of our low leaf littter, low volatile oil containing grasses.  These plants have been raised in greenhouses for over a year with timed watering of 1" per month.

Choosing the right green roof plant will ensure your Florida or Southewastern Green Roof's success.  Call Kevin at 904-294-2656 for details.

Green Walls - Living Walls - Green Roofs - What Plants do I use?

Tip Of The Day.

How do I learn about what plants do best for green roofs in an area?  Begin by driving around and identifying those volunteer species growing naturally in building walls and roofs around your city.

Some will work, some won't - however this practice is a good start to understanding what plants do best without irrigation and in minimal soil.

Call us with questions on your green roof project.

Green Roofs - Irrigation and Green Roofs - Green Roofs for Florida and the Southeast

As I travel across the Southeast, I take the opportunity to stop and study plants growing in different places within the urban core.  I was amazed at the variety of plants growing out of crypts and other structures in New Orleans.  Hot, dry and desolate, the stone structures successfully supported a number of plant species that apparently had been growing for quite some time.  Just goes to show - you do not need to irrigate a green roof.....

Irrigation and Green Roofs - Green Roofs for Florida

The green roof test panel shown here is one year old.  We are preparing the unit for hurricane wind tunnel testing.    The only irrigation the roof panel has had is rainfall, and survived a very dry winter and spring.  Green roofs present a different growing environment for plants than do the ground.  No matter how rocky or little soil there may be, the ground offers a consistently cooler place for roots to exist.  A three inch thick extensive roof soil layer can reach temperatures of 140 degrees F or higher while the ground temperature is significantly lower.  So for plants to survive on a non-irrigated green roof, they must be carefully chosen.

We are raising a new breed of plants in the greenhouse where they are exposed to growing conditions much like those to be experienced on a roof.  Heat and prolonged drought.  With trials well into a year now, the plants go through prolonged leaf impact, however when finally brought out and exposed to rain, the bloom and grow.  Importantly, we look at the potentially for flammability when using plants with dried leaf matter or leaf litter.

One interesting quality we are seeing more and more of is the ability for plants to absorb humidity here in Florida.  Fortunately, even when the temperatures are torrid, the air relatively humidity may be quite high.  Air humidity can make the difference between a plant dying and a plant surviving a long period of non-rainfall.

Finally, with water shortages here in Florida and watering restrictions in place by municipalities and water management districts, why would a green roof designer recommend irrigation?  It is because they do not understand the 'right plant, right place' concept.  We have been working on green roofs for many years and understand those plants that work and those that do not.


Call us to discuss your next green-roof project!  Kevin 904-294-2656

Green Roofs for Florida - Sailboats can have Green Roofs also....

Bayou la Batre, Alabama - Sailboat Green Roof Supreme!  Enjoy!

Kevin...904-294-2656

Watching Green Roofs in Florida Evolve Over the Years...

It is amazing to watch the plants on a green roof move, find their perfect niche and grow over the years.  The photo here is of a sedum growing down across the roof and into the gutter, then overflowing the gutter and cascading down vertically.  Adding volumetric green to the urban core with Florida Green Roofs! For more information on green roofs, call Kevin Songer at 904-294-2656.

Non-Irrigated Green Roof - 1 Year and Still Going Strong at UF Test Center

Call Kevin for more information on your light weight green roofs 904-294-2656.

Green Roofs For Florida!

Florida Green Roofs - Rainy December

Florida's weather has been at it again.  Drought and more drought then rain and more rain.  Very hot days then cold nights.  Smothering humidity then dry as dry can be.  Tough on the plants.   MetroVerde's MVGR3 system keeps the green roof plants irrigated but not too wet.  Designed for light weight, the engineered soil medium is typically no more than 2 inches thick.  Works well in Florida's harsh climatic conditions.  See www.metroverde.com or email judy@metroverde.com .

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

Bonsai style preparation for green roof plants in Florida is time consuming yet delivers results and is worth the time and effort. MetroVerde green roof plants are grown with no additional fertilizer and rely on native rainfall events for irrigation. The plugs shown above are one year old, having spent their life growing under conditions similar to what they will experience on the roof.

The plants shown here are Allium species - and we are experimenting with the native 'nodding onion' found growing across the southeastern United States.

I highly recommend anyone considering a vegetated green roof to plan well in advance and 'bonsai' the plants - acclimating them to the same harsh environment they will spend their life in on top of a roof.

Remember the 5 'H's of the Southeastern US and Florida - Hurricanes, High Humidity, Heat Extremes (Pressure cooker style), Hard Frosts , and High Winds that dry and dessicate plant leaves.

I wrote a blog entry last year about sprouting green roof plant seeds on the roof they will be planted upon - and though not always practical. In any event, growing the plants under non-fertilized, non-irrigated conditions until they are solidly established is a solid approach to plant success once on the roof.

I've seen too many vegetated roofs fail after the designer and installer use plants pumped full of fertilizer, not hardened off and used to significant amounts of irrigation. Once on a roof, the plants experience shock.

Natives are great - adapted native species excellent too.

Remember, prep your plants long before planting on the roof.

Kevin

Atlantis Living Walls - Living Walls for Florida, Vertical Green

Here is an interesting video of Atlantis Water Management System's Living Wall Concept. The design is solid, especially as the frame is made from 95% Post-Consumer recycled material - good LEED Compliant stats.

I'd make a few changes - such as setting the living wall frame off from the stucco wall by at least 4 - 6 inches and seal any penetrations for anchors with a good low VOC sealant.

Irrigation concept is good too, however I'd certainly capture the water as it exits the bottom of the system to prevent Slip and Fall litigation - you know how prone us American's are to lawsuits...look at the puddle at the end of the clip - Res Ipsa Loquitur.

The extra width will serve to provide stability - especially on free standing walls.

Any ideas how they could be used to treat stormwater?

Green Roofs for Florida - Irrigation required? No!

Now, many green roofs are not garden roofs. They are not full of lush, tropical vegetation with nitrogen fertilizers added and irrigated with water that should be charging our aquifers. The latest argument for irrigation of green roofs - is - it is OK if the irrigation water comes from recycled stormwater. Sounds good, right! But how many of proponents of rainwater recycling actually have had rainwater systems in place for some time? If they do they will tell you that the cisterns are empty most of the time! Yes, we have an annual rainfall amount of well over 50 inches per year, but we also have extended periods of time where there is little if any rainfall.

So the proponents of irrigated green roofs say - use city water backup!

I thought we were in water conservation mode here. Watering restrictions, etc...

Just don't irrigate your vegetated roof. Use native species! The other day on a conference call an engineer referred to the native species of plants as 'Weeds!"

It is all perspective. I like the thought of using native species, not irrigating and still having a great vegetated roof.

The above photo is a test panel at UF that has been sitting in a back lot with less than an inch of soil average for almost a year with no irrigation or fertilizer and is still functioning to drink and clean stormwater and provide habitat for pollinators, etc...

No, it is not Jungle Gardens. But it is a thriving, functioning Green Roof! Remember - there is a difference between Intensive Green Roofs that are irrigated, weight 10 times as much or more and cost ten times as much or more - and require massive structural support - and Extensive Green Roofs that are light weight, non-irrigated, non-fertilized and can be put on simple structures.

Another Green Roof in Florida - with Natives & Non-Irrigated

Corie's roof is planted with Florida Natives. The weight is approximately 10 lbs per SF and the roof is non-irrigated. We will post pictures as the roof plantings fill in with the growth of the native allium seeds.

Why irrigate green roofs????

Another Reason Not To - Click Here...

Green Roofs, Irrigation, Florida & Hurricanes

Hurricane - High Winds & Non-Irrigation Tests for a green roof test panel. We are collecting data, working with a major university to measure hurricane effects on a non-irrigated, lightweight extensive green roof.

The test panel is a 4' x 10' simulated roof capable of being raised and lowered from a flat elevation to a forty five degree angle.

The vegetated portion is non-irrigated and less than one inch thick.

The panel is being tested under hurricane wind speeds in a wind tunnel. It is also under study for plant growth and survival characteristics under a no-irrigation environment where the insulating qualities are being measured also.

Stay tuned for more information!

Green Roofs in Florida and Irrigation. Is irrigation really necessary for green roofs in Florida?

Here we go again! The draft stormwater manual compiled by the Florida Department of Environmental Protection states that 'Green Roofs in Florida must be irrigated.'

The above statement is simply incorrect and is not a statement we should be hearing from the agency stressing xeriscaping and water stewardship!

I am immediately shut off when I even bring up the topic by many.

Why?

I don't know but it is true - Florida Green Roofs can prosper and thrive even without irrigation.

The roof above has done so beautifully! And in-fact is growing water loving sedges this summer (though I imagine they will die when the dry winter hits) - I suppose birds or the wind dropped seed.

Choose your plants wisely. Plant green roofs to survive without irrigation. Be water wise!

Florida Green Roofs, Roots, Liners, Life Expectancy and Shingles

Yesterday I removed one of the original green, vegetated roofs we had installed in Florida - to replace with different plants - an herb garden type.

I was amazed at how the green roof plant roots had attached themselves to the fabric, creating a strong and binding weave - an important consideration here in Florida's hurricane prone environment.

The shingle roof underneath actually looked newer than the day, years ago that I installed the green roof.

Another example of how green roofs can protect the underlying roof membrane (especially non-irrigated green roofs!)

Kevin