A couple of years ago, Dawn wrote a brief survey of the widening intersection of art, building, horticulture and environmentalism. Since that time, numerous fantastic concepts, designs and urban interventions have brought greenery to public and residential spaces in innovative ways.
Tokyo-based PingMag recently interviewed Patrick Blanc about his Vertical Gardens, some of the most dramatic, large-scale green facades around. He could rightfully be called a landscape "starchitect," the likes of Gehry or Holl, with some installations in glamorous locales like Girbaud in Paris, a fashion show for Jean-Paul Gaultier, and soon a skyscraper in Kuala Lumpur and the Doha Office Tower in Qatar.
Blanc describes the materials and building process for his structures, which brings up the commonly encountered conflict of artistic intention and actual practice. The vertical gardens are made with PVC sheets -- PVC (polyvinyl chloride) being an extremely versatile and common material that comes under extreme criticism for being fossil fuel-intensive, chlorine-heavy, non-recyclable and responsible for dioxin releases.
The Vertical Garden is composed of three parts: a metal frame, a PVC layer and felt. The metal frame is hung on a wall or can be self-standing. It provides an air layer acting as a very efficient thermic and phonic isolation system. A 1cm thick PVC sheet is then riveted on the metal frame. This layer brings rigidity to the whole structure and makes it waterproof. After that comes a felt layer made of polyamide that is stapled on the PVC. This felt is corrosion-resistant and its high capillarity allows a homogeneous water distribution. The roots are now growing on this felt.
Watering is provided from the top with the tap water being supplemented with nutrients. The process of watering and fertilisation is automated. The whole weight of the ‘Vertical Garden’, including plants and metal frame, is lower than 30 kg per square meter. Thus the Vertical Garden can be implemented on any wall without any size or limitation of height.
That factor aside, Blanc's process is quite scientific and deeply researched. He conducts studies in tropical areas, primarily on "understory" plants which receive minimal sunlight beneath the rainforest canopy, and can thus be presumed to grow in humid indoor areas where sunlight is limited. He figures out which species will thrive in the environment for which he's commissioned to design, then configures the garden such that it's self-sufficient, requiring only quarterly maintenance.
So far, I've not heard about this kind of approach to greenery achieving traction on an average residential scale (and by average I mean in terms of cost as well as size). Given that most people just use potted plants inside, it doesn't seem like a particularly necessary addition to one's home, though it would be a great decorative strategy and I'd love to hear if anyone's done it DIY-style. In more institutional and commercial settings, a giant wall of ferns and succulents can do wonders as a natural air filtration system and a general atmosphere improver and mood-enhancer. Any botanists want to come rig a vertical garden at the Worldchanging offices?
