Words by Adrian Higgins, The Washington Post
The desire to clothe buildings, fences, walls or any vertical plane with plants is a long-held ambition of gardeners and goes back at least to the Hanging Gardens of Babylon.
In recent years, another type of vegetative art has emerged, called living walls or green walls, and which relies on pockets to hold the roots. Under the guiding hand of a bold designer, they can take a repertoire of fairly ordinary plants and turn them into a tapestry of stunning effect.
One of the champions of this horticultural art form is the French designer Patrick Blanc, whose commissions include the side of a five-story building in Paris transformed from bare stucco to a vertical jungle named L’Oasis d’Aboukir.
Many living walls are constructed either in balmy places such as Florida or indoors, allowing the use of tropical plants, including some of the leafier houseplants.
Building one outdoors in a temperate climate forces the use of hardy plants. In his Paris project, Blanc used not just hardy perennials but also a few shrubs. The palette includes bergenias, pinks, cranesbill, hypericum, liriope, hostas, fatsia, and even nandina and yucca.
Such vertical gardens require expertly engineered systems of support and ways of delivering water and nutrients. They also require large quantities of plants.
“I don’t think it’s a do-it-yourself sort of thing,” said Ed Snodgrass, a grower of green-roof plants in Street, Maryland. “You have to be pretty slick to take on a do-it-yourself pocket wall, with all the systems it requires.”
The curtain of vegetation veils its workings: Custom armature, a hive of planting cells, a computerised irrigation system and supplemental lighting. Many skip the soil – the plants grow in synthetic felt or the like and are watered and fed hydroponically.
If you want a sense of the challenges and rewards of the vertical garden, consider the Green Wall at Longwood Gardens in Kennett Square, Pennsylvania. It was the largest living wall in the United States when it was built in 2010 and is used to decorate a curving corridor of individual restrooms. The garden consists of two walls – they face each other – and each is 13 feet high and 360 feet long.
The wall is a beguiling composition of 33,000 plants in contrasting textures and shades of greens. By using mostly ferns, flowering is kept to a bare minimum. It’s designed as a break from the floral extravaganza in the East Conservatory. “It’s the sorbet in a great meal,” said its gardener, Lauren Jenkins. “This space is a respite.”
For the viewer that is, not Jenkins. With her team of four volunteers, she is continually grooming and trimming and making sure that the plants are happy.
Companies have emerged to cater to this market. Employers see value in living walls as ways of beautifying office lobbies and bestowing tranquility in an otherwise harried environment.
Michael Furbish, of Furbish in Baltimore, has installed approximately 40 living walls over the past eight years. “We have a lot of people who see our walls in commercial applications and say, ‘What if I want one, two feet by two feet, or three by three, in my kitchen. Can I do that?’ ” But scaling down doesn’t negate the need for custom installation, sophisticated irrigation and other systems, so “it becomes prohibitively expensive,” he said.
Featured Image: Becca Mathias Photography – Longwood Gardens