Green Roofs, Deciduous, Dormancy and the Color Brown

Though not my favorite time of the year Winter always brings the welcomed sigh of relief to her pallet of colors with the appearance of a special deep brown.   Anticipating next year's vigorous renewal,  brown adds the fourth dimensional depth of time to the remaining sprays of green.

MetroVerde Green Roof Panel

Winter on the green roof is no different.  In fact, winter on the green roof allows for a period of correction, recollection and hope.

Of course Winter here in Florida is mild compared to what others across the world experience with respect to duration, we still get cold enough here to induce dormancy and deciduous characteristics in   many plant species (If you call a low seasonal temperature of the mid-20's F or - 6.5C cold).

Aptenia on a MetroVerde green roof

While it is always good to look out across a living roof and see vast expanses of green, deciduous brown can be reassuring.

Without the annual browning of the fast growing C3 plants the living roof would become a jungle, restricted in biomass output only by available water supply.  However after the first hard freeze, dead biomass can be removed from the living roof to expose C4 and CAM plant type successes, successes to be built upon for subsequent years design and growth planning.

C3 and CAM plants across a sloped green roof in Florida

For living roofs in dry and arid climates experiencing sub-freeeaing winter temperatures, winter visualness can be designed to allow for striking contrast of textures and colors.

Catherine Burkee, Educational Director for Breaking Ground Contracting here in Jacksonville has a wonderful video and note of the Breaking Ground Green Roof she recently posted about the changes of seasons as seen on their living roof.

I am looking forward to a great 2012 for living roofs around the world!