Excerpt taken from article originally published in Organic Gardener by Helen Cushing, February 2020
The green building revolution
‘Living infrastructure’ is the preferred name these days for what most of us would just call “plants on buildings”. Alongside rooftops, vertical gardens are the other direction (pun intended) the living infrastructure innovators are refining and developing.
Ivy-clad walls, climbing roses, window boxes, espaliered fruit trees, just like sod roofs, have for centuries graced buildings both grand and humble. But the new wave is going further, adopting the idea of ‘biophilia’.
In his book Nature by Design, the late Yale professor Stephen Kellert, describes biophilia as “the inherent affinity people have for the natural world”.
Whereas previously such a theory may have been an unstated and accepted part of life, our biologically lonely concrete jungles are increasingly separating us from nature. Recognition that this is not good for us, that it is making us sick and unhappy (and therefore is not good for productivity) is propelling the living infrastructure boom. Just as technology made the concrete jungle possible, so technology is enabling the greening of that concrete.
Sydney’s sky jungle
Sydney boasts one of the world’s tallest vertical gardens, award-winning One Central Park, a 150m high oasis in the desert surrounding Central Station. The planting design is by renowned French botanist and artist Patrick Blanc, an original proponent of vertical gardens. Inspired by the ability of plants to grow naturally without soil on vertical surfaces such as trees and rocks, Blanc developed a felt-based growing system to bring the lush fecundity of nature into barren cityscapes.
One Central Park uses some 250 plant species, mainly Australian, many found on cliff faces in the Blue Mountains, west of Sydney. Blanc’s ambitious vision to evoke this natural experience in the centre of Sydney was a challenge to install, but from 2012–14 Sydney company Junglefy took it on, developing world-first installation methods to ‘plant’ the 1120 square metres of garden.
“One Central Park was the first of its scale, globally,” says Junglefy founder Jock Gammon.
“It disproved the naysayers.”
A cascading tangle of ferns, vines, succulents, flowers, strap-leaved clumpers, and more, create a lush skyjungle in one of Sydney city’s busiest streets for approximately 5,300 residents and 1,750 workers.
There are many pragmatic environmental and economic reasons to love this and other living infrastructure: shading and insulating building surfaces; cooling the surrounds through evapotranspiration and purifying the air by storing carbon dioxide; producing oxygen; removing toxins; and even ‘harvesting’ airborne particles. The latter is a heavy burden traditionally borne by street trees and parks.
The building complex also provides research opportunities for students across the road at the University of Technology Sydney. Projects include researching the biodiversity enhancement of the gardens, and the feasibility of anaerobic organic waste management in the city. The latter includes the abundant cuttings from the gardens and food waste from the numerous kitchens within the building.
Another excellent example of city greening is on a multistorey carpark in Sydney’s Manly Vale, where Junglefy has used green walls to transform an ugly utilitarian structure on a busy road into something bright and beautiful.
Leaving Sydney, let’s return to rooftops. In Melbourne, the roof garden of Victoria’s newly renovated Parliament House restores a patch of biodiversity to the CBD. Designed by Paul Thompson, a leading light in the use of indigenous plants in landscape design, the garden features drifts of native grasses, wildflowers and small shrubs, planted around a winding bluestone path.
The Burnley Campus of Melbourne University has installed three green roofs, one for research, one for demonstration, and a third for biodiversity, fostering animal life. Trials include different depths of growing media, irrigated and non-irrigated beds, the use of endemic species, and a wetland.
Walls that breathe
Air pollution is not only a street problem. Sick building syndrome (SBS) is prevalent in artificially lit and air-conditioned buildings which are generally outfitted with synthetic building and furnishing materials that quietly outgas fumes known as volatile organic compounds (VOCs).
We add to the problem by breathing out carbon dioxide, which builds up in our sealed offices. Fatigue, headaches, eye, nose and throat irritation, asthma and nausea are just some of symptoms. Indoor pot plants, like street trees, are often grown to purify and heal the air while soothing our suppressed primal, biophilic urges.
Going further, many buildings are incorporating green walls on both a small and large scale, with cascading plants greening atriums and courtyards.
Junglefy has developed an ‘active breathing wall’: a modular green wall system designed specifically to tackle poor indoor air quality. To the untrained eye it just looks like a lovely green wall, but hiding unseen is a small fan that draws the air through the growing medium and across plants at quite a rate.
The planting medium, which is high in coconut fibre, traps particles and VOCs while increasing carbon dioxide draw down by 80 per cent. The particles and VOCs are broken down by bacteria in the planting medium. The air comes out the other side of the wall oxygen-rich.
Additionally, the wall absorbs noise, humidifies the dehydrated air-conditioned atmosphere and reduces the need for air conditioning by up to 33 per cent.
“The microbes are in a symbiotic relationship with the plants,” says Junglefy’s Jock Gammon.
“Both are needed for the breathing wall to survive. It’s the bacteria, not the plants, that break down the VOCs and particles.”
Perhaps the ultimate test of Junglefy’s breathing wall is a new installation on Sydney’s Eastern Distributor Motorway coming off the Harbour Bridge. Panels of bold plants have been installed in a world-first research collaboration backed by the NSW Government to determine the effectiveness of green walls in tackling air pollution.
…this article continues.