At the end of the 1960’s, when Blanc was a teenager, he conceived his first vertical garden as a kind of biological filter for his tropical aquarium. Later, during his college years, he visited the tropical jungles of East Asia, where he observed up close his beloved aquatic plant species.
Patrick Blanc is a French botanist known throughout the world as the mastermind behind the vertical gardens movement.
It was then that he decided to devote himself to the study of tropical botany. His passion for the adaptive strategies of the vegetation of the tropics was the subject of his thesis, which won the Botany Award of the French Academy of Sciences, in 1993. It was during these years that Blanc developed his concept of vertical gardens, which he eventually patented.
“Do plants really need soil to survive and thrive? The answer is no because the soil is no more than a mechanical support. Just water and minerals are essential for plants, together with light and the carbon dioxide required for photosynthesis”, explained Blanc when asked about the topic.
Biologists and other specialists in the field know that plants in their natural habitats grow on vertical surfaces, especially when water is available throughout the year. The same occurs in tropical forests, where plants can grow on tree trunks and branches, as well as on limestone cliffs, caves, waterfalls, or on the slopes of the mountains. These situations, which in principle may seem surprising, are the ideal habitat for many plant species. Therefore, following the dictates of nature, it is possible for plants to grow vertically, almost without soil surfaces, provided they have a permanent water supply.
For Patrick Blanc, walls and plants are an excellent combination, but only when there is a good design and engineering because if the roots grow inside of a man-built wall, they can seriously damage the structure and finally destroy the wall. “That is precisely what happened with the beautiful temples of Angkor in Cambodia,” says the botanist.
To avoid this inconvenience, Blanc conceptualized his vertical gardens as a second skin for the buildings, where the roots of the plants would spread only on the surface of the vertical structure, leaving intact the inner wall. That way, plants and architecture interrelate in perfect harmony. According to Blanc‘s idea, the plant´s support system is very light and can, therefore, be implemented on any wall, regardless of size. His vertical gardens can be configured both indoors and outdoors, and the selection of species is determined by the climatic conditions of the environment.
Blanc´s vertical gardens are composed of three parts: a metal structure, a sheet of PVC and a layer of a special felt. The metal structure hangs from the wall or can be left standing; it provides a layer of air that acts as a very efficient thermal and phonic insulation system. The PVC layer— 1-inch thick—completes the metal construction. This sheet provides rigidity to the structure and makes it waterproof.
The roots grow smoothly on the felt and the irrigation is carried from the top. The entire weight of the vertical garden— including plants and the support structure— is less than 5 pounds per square foot. Therefore, Blanc´s vertical gardens can be installed on a wall of any size or height.
Vertical gardens are a haven for biodiversity and a cleansing system for polluted cities. Their thermal insulation effect is very efficient in reducing energy consumption in buildings, both in winter and in summer. It is also an effective way of cleaning the air because the roots and all microorganisms associated with them act as a cleansing factor for the ecosystem.
Thanks to Patrick Blanc’s innovative concept, nature is integrated into the urban architecture in a harmonious, flawless and natural way. These wonders can be appreciated in various places, from the lobby of the Icon Hotel in Hong Kong and the spectacular Dussmann das Kultur Kaufhaus bookstore in Berlin to the beautiful resort Life Marina in Ibiza, the Grand Palais in Paris and the Perez Art Museum Miami. ■