Friday, July 25, 2014

Florida Green Roofs - Know Thy Plants!

Florida summertime is hard on green roofs.  Not only are roofing membranes subject to intense weather challenges, green roof plants also are subject to intense biological and meteorological assaults.
Summer humidity may quickly kill Florida green roof succulents
We have posted notes about Black Rot fungus before here on this blog.  It never fails though that every summer persons will contact me asking why their succulents are turning brown, black or rotting.
Florida green roof succulents battle the Black Rot fungus every summer
The simple answer is to use Florida native plants (preferably evergreen species but a mix of deciduous plants will work too, depending on the green roof location in the state).  Here in Florida native green roof plants usually far outperform horticultural succulents.
Florida green roof succulents rarely become the dominant green roof plant and usually die out
Florida summers bring maximum humidity and maximum temperatures.  With daily afternoon rain showers most rooftops become pressure cookers, steaming green roof plants like vegetables in a hot wok.  If you do not intimately understand Florida roofs and how plants preform there (and this only comes from hands on learning, failures and successes are the best teachers) then your roof design may quickly end up devoid of plants as you stand there, helpless, watching the succulents literally dissolve in the heat and humidity and fungus attacks.

Tropical green roofs are a challenge.  We have listed some great green roof native plants here.

Know how your plants will perform in a pressure cooker before specifying them on a green roof here in Florida.

Wednesday, July 9, 2014

Why Florida Green Roofs Are So Environmentally Important

Here in Florida surface water can directly flow into the drinking aquifer below the ground in many places.  Here is a video of storm water flowing down into the ground through a karst connection to underground caverns after a recent rainfall event.
Cleaning rainfall runoff with green roofs and other urban greening projects before the stormwater reaches our drinking water supplies makes good sense.

Avoidance of pesticides, herbicides and lawn fertilizers and chemicals is good not only for our environment but also supports a cleaner and healthier place to live in.