Friday, February 11, 2011


I envy the famous French botanist Patrick Blanc's mandarin-length fingernails; he surely must use them as tiny gardening tools when collecting and transplanting tender young plant specimens. Creator of a very practical and successful vertical gardening system, the botanist and researcher with green tinged hair is known the world over in urban landscaping and architectural circles for his patented technique to grow vertical ecosystems without soil. With his simple method and a steady supply of water and nutrients, Blanc can turn any bare wall into a refreshing mass of green.

A plane tree  framed by Patrick Blanc's vertical garden at Les Halles  in Avignon, as seen from a terrace café. 

Blanc, a plant lover since childhood, then scientist at the France's Centre National de la Recherche Scientifique, studied the way plants colonize vertical surfaces and developed his idea on how to plant on city building façades. This Indiana Jones of the plant kingdom has trekked all over in search of plant species that thrive in extreme gravity-defying conditions. Either clinging to cliffs or growing on boulders and dead tree trunks, such plants have wide-ranging shallow root systems which allow them to stabilize on only a fine layer of humus or moss.

Blanc once told me in a interview that because the materials are so lightweight, his technique can be used on buildings of any height. Patented in 1988, his vertical gardening system has been put to the test for more than 20 years.  How does it work? The plants are inserted into slits in a sheet of synthetic substrate mounted on metal frames, and a watering system releases diluted nutrients as needed. Importantly, an air space and a layer of expanded PVC separate the substrate from the supporting wall to protect the building's surface.

How can plants grow without soil? Blanc explains that soil is merely a medium in which plant roots fix themselves for stability; all the minerals and nutrients necessary for growth are transported by water in the soil and absorbed in soluble form by their roots. When creating a vertical garden, Blanc selects species suited to the climate and lighting conditions.

On city walls from New York to New Delhi, Blanc's luxuriant gardens are living canvases which are not only beautiful, but useful. They act as insulation to minimize a building's heating and cooling needs and fight pollution by reducing toxins in the air through photosynthesis and absorption, all without taking up valuable horizontal space.

Read and see more about Patrick Blanc and his latest vertical gardens by clicking here.

avoir la main verte:  to have a green thumb
mur végétal: vertical garden

The above text contains substantial excerpts from an article I wrote which was originally published in France Today magazine, July/August 2005.

Text & photo ©2011 P.B. Lecron

1 comment:

  1. What a wonderful terrace, I love it when I see something growing where growth defies explanation. Plants are more resilient than people many times over.