Green Roof Plants - Food, Fiber and Medicine

Choosing the right green roof plants can sometimes be a challenge for even the most experienced green roof designer.

Over the next several days we will be discussing approximately forty different species suitable for green roofs in climates similar to those found here in Florida - Arid, Rainy, Hot, Humid, Cold, and Windy.

We will be discussing five new species each day.

The basic principles each green roof plant possesses include:

* Drought tolerant
* Hardy against innundation and flooding
* Possesses qualities of either food, fiber or medicinal traits
* Social benefit from beauty
* Non-invasive or pest qualities
* Native species to region
* Provides food, forage or communal habitat to wildlife
* Cleans stormwater
* Good plant for sequestering Carbon

The first five plants we will discuss are:


Important Food and Fiber Green Roof Plants

Moringa oleifera

Moringa is truly a wonderful plant and though it is somewhat frost-tender, attempts should be made to grow this plant in at least one or two spots on green roofs.  Moringa is considered one of the primary plants to be used in efforts to eradicate poverty and malnutrition.  Most parts of the plants are edible by either humans or cattle, contain up to 60% protein and also contain all the essential amino acids and many vitamins and minerals.

Moringa grown in extensive green roofs will react much like Yucca species and acclimate to the reduced soil amounts with smaller habit and form size.

Moringa tolerates drought as well as innundation.  Moringa has been used succesfully as an important pollutant removal mechanism for cleaning water and stormwater.

Though not for every green roof, due to the ethnobotanical and economic importance of this plant, attempts should be made to determine whether or not Moringa is a viable green roof species for your project.
 
Cajanus cajan

Another important green roof plant is the pigeon pea, Cajanus cajan.  Pigeon pea too is somewhat frost tender but is considered root-hardy in many areas of Florida.

Pigeon Pea is also used for food and contains significant amounts of protein as well as the amino acids, methionine, lysine, and tryptophan. 

 Like Moringa, Pigeon Pea may not work for every green roof, however due to the ethnobotanical and economic importance of this plant, attempts should be made to determine whether or not Pigeon pea is also a viable green roof species for your project.

Allium cernuum

Most alliums make good green roof plants.

They are evergreen, drought tolerant and possess attractive flowers.

The medicinal and food uses of alliums are well documented.  Current studies include uses in horticultural integrated pest management programs.  Though Allium cernuum is not considered native to Florida, the species is well adapted, non-invasive and a pretty addition (with it's purple flowers) to any Florida green roof.

Allium tuberosum

Allium tuberosum is also more commonly known as garlic chives.  This species is a backbone of many green roofs.

Extremely drought tolerant, Allium tuberosum has been know to survive four to five months of primary drought.

This species is used medicinally and for food.  The white showy flowers offer fall color.

Allium tuberosum should be considered as a primary species in any Florida green roof project.

Florida Native Plants for Green Roofs

Allium canadense

Much like Allium tuberosum, Allium canadense is a drought tolerant species suitable for green roof applications.

Unlike Allium tuberosum, Allium canadense is considered a Florida native plant species and can be found growing almost anywhere across Florida. The species can frequently be seen growing in ditches and alongside roadways in either wet or dry areas.

Allium canadense should also be considered a primary green roof species suitable for Florida projects

We will be discussing more species over the next few days.

Feel free to add your comments or  email us with your questions here.

Happy green roofing.

Kevin