Tuesday, February 1, 2011

Blending C3 and C4 Plants

Remember our discussion about green roof plant photosynthetic metabolisms - the C3, C4 and CAM plants?

C3 Plants give quick coverage to Green Roofs yet may not be as long lasting and are not as resilient to heat and drought.

C4 Plants are slower growing because their photosynthesis occurs differently, using multiple cells and processes for the Calvin Cycle.  C4 plants can typically endure drought better than most C3 plants.

The below photo shows how C3 and C4 plants can be integrated for quick color and long-term structure.  The C4 allium (plants with thick sprouts approximately 50mm tall) are just beginning to break through the C3 groundcover species.

Quick green color and subsequent height and green structure.

C3 and C4 Green Roof Plants - Allium canadense

This photo was taken atop the green roof on our new rabbit hutch.  Approximately 1000 garlic cloves were planted in the roof as a trial for the plants efficiency with integrated pest management benefits.

The allium also possesses beautiful flowers.

There are many species of allium, lots of native varieties too.  Allium is a great green roof plant, one that hardly ever dies but not too aggressive.  Allium canadense, or nodding onion supports native biodiversity as well and can be found growing in its native habitat across the US and Canada!

Pollinators and butterflies love this plant and I've even watched hummingbirds visit the flowers on a regular basis.

More photos later as the alliums continue to grow.

Email us with your questions and comments and as always,  Happy Green Roofing!


1 comment:

Alejamuel Sultz said...

Plants on the green roof generally provide a new habitat for insects and birds, too. Allium, is indeed one of the preferred plants for green roof. You can add “yarrow” for that, too. When it grows and it blossom into an attractive flower, it will surely adorn your green roof.