Humans are happiest around plants, but the cities where most people live are devoid of nature. Walls provide the perfect canvas for more urban greenery.
Urbanisation is one of the trendiest things right now — literally. In 1950 only 30% of the world’s population lived in cities, 65 years later it swelled to 54%. To accommodate all these extra people, cities are chewing through green space. Forests and farmland on the boundaries become suburbs, backyards are subdivided into oblivion and parks vanish underneath skyscrapers.
As a result, cities suffer from a chronic shortage of plants with serious consequences. The environmental problems spawning from urbanisation include air pollution, loss of habitat, heatwaves, and high carbon emissions from energy used to cool buildings. Increasingly, research is confirming what many instinctually feel: humans need to be around plants to be happy and healthy.
A little more of the green stuff in cities would have huge benefits for the environment and our mental and physical health. But where could it go? There is very little unused space in the inner city where many people live and work, and land is at a premium. The economic benefits of an office tower are obvious; the value of a grassy meadow is less tangible.
One thing there is plenty of in cities is blank walls — and they provide unique opportunities for greening.
Adventures down alleyways in Melbourne
I walked down every street and laneway in the heart of Melbourne looking for plants going up walls during an internship at the City of Melbourne. Parks, street trees, and increasingly innovative green infrastructure such as vertical greening and roof gardens are valued for their contribution to the liveability of the city. The findings of my adventures will inform City of Melbourne projects like Green Your Laneway, which is turning four desolate laneways into leafy oases.
Once you start paying attention, there are green walls around every corner. The internship sparked an obsession for tracking them down and spawned an Instagram account: @plantsgo_up. I’ve amassed a collection of photos, and stories from interviews with gardeners, building managers, business owners, researchers, and innocent bystanders. I’m certain — as much as a scientist can be — that everyone agrees plants make walls look better.
Walls are better when they’re covered in plants
The biophilia hypothesis coined by E. O. Wilson describes humans as being deeply drawn to nature and living things. While it’s a very difficult concept to prove, we do seem to do better around plants.
A seminal study by R. Ulrich in 1984 found that hospital patients with a view of trees recovered from gall bladder surgery quicker and used fewer painkillers than those facing a brick wall. Simply staring at a photo of a grassy rather than concrete rooftop for 40 seconds can boost your attention span. Given a choice, which would you prefer? Is it even a fair question?
Things get really exciting when people with the power over walls see the value in plants. Andrew Gay, Grounds Supervisor at the University of Melbourne, is a firm believer in using foliage to cover up ugly buildings. The university has an unfortunate abundance of 1950s to 1970s architecture, a time when stark walls of yellowish-brown bricks were all the rage. About 15 years ago Andrew planted a Boston Ivy (Parthenocissus tricuspidata) to hide one such wall. The result is an impressive green facade (above, right), which is the technical term for a wall covered in climbing plants.
The Old Botany building is appropriately the greenest on the University of Melbourne campus. It would be consumed by plants if it wasn’t pruned twice a year, although a stray tendril once snuck its way into a quarantined lab through a cracked window. I thank frequent strolls around the building for preserving my sanity while I was writing a master’s thesis.
Work it greener, makes us stronger
Having access to nature in the workplace has been credited with lowering stress and increasing job satisfaction. Businesses in pursuit of happy, productive workers are tuning into this research and incorporating greenery in offices on a massive scale.
The new Medibank headquarters in Melbourne are a verdant example. Roof gardens, a communal veggie patch, 2,300 indoor plants and 1,326m2 of climbing plants reaching up 16 storeys surround employees in greenery. On the outside of the building, two 20m-high living walls add a bit of jungle to a stale city street.
The dense green tapestry is made of 11,600 individual plants growing out of a specialised container system attached to the wall. Similar to a normal garden bed but vertical, living walls include artificial soil, irrigation and drainage. Confusingly they are also sometimes called green walls, a term for any wall covered in plants, including green facades.
The plants used for the Medibank building were carefully chosen to be capable of withstanding the challenging conditions of the urban environment. The living walls are shaded for most of the day so ferns, bromeliads and other species from naturally dark environments such as the rainforest floor were selected. On the other hand, the green facades wrapping three sides of the building are exposed to lots of light, wind, and heat. The six climbing plant species used here proved they could grow well in these conditions in research trials.
Medibank was driven to go green after research they commissioned found bad workplace environments led to negative health impacts for employees, and cost employers in low productivity and high turnover. Finished in 2014, the building was a team effort between architects Hassell and urban landscape experts Fytogreen. Since moving in, the company reports absenteeism decreased by 5% and 66% of staff feel more productive.
An end to blank walls?
In October 2016, the international community will meet at Habitat III and set the global agenda for sustainable urban development. Worldwide, green walls are being investigated as a way to combat the ills of the nature-deficient environment humans have built for themselves. Explaining their benefits in real terms like human health, ability to cool buildings and reduce air pollution justifies the cost for businesses, building owners and governments.
Green walls can and should play an important role in the creation of better, people-centred, and environmentally sustainable cities.
Edited by Ena Music