Planting for all the right reasons
A plant is better than no plants. But our city streets deserve more than a few groundcover species in a sea of mulch, which won’t bring us the well-researched benefits of immersion in dynamic nature.
By Jon Hazelwood
A prevailing – and noble – sense of trying to restore generations of environmental damage has led landscape architects to preference plants native to the specific site’s pre-colonial condition. Unfortunately, in urban environments, this can be at the expense of biodiversity and resilience – and beauty.
Australian garden designer and ABC TV and radio presenter Michael McCoy described this mindset in our recent conversation for the Hassell Talks podcast. “We carry a huge amount of remorse for the damage we’ve caused and continue to cause,” he says.
“That leads to a restoration mentality of attempting to try and restore how things were.”
Client requirements and local authority mandates are often also behind the decision to prioritise natives over all. And as is often the case, concepts that ambitiously included hundreds of local species are realised as a perfectly-spaced monoculture – the beautiful concept diluted by the lenses of policy, maintenance, availability and our own planting knowledge.
For example, a patch of coastal heath in Sydney, Australia, reveals a stunning diversity of species that are structured, self-regenerating and in constant seasonal change. A ground plane of delicate forbs and wildflowers in a sea of grasses, where mounds of small shrubs emerge below Grass Trees and Grevillea, under a canopy of large and small trees - Eucalypts, Banksias, Corymbia. The assorted species are mixed and layered together, not corralled into separate blocks of single species, planted at three square metres.
To try to replicate wild nature in an urban setting is impossible, but to abstract it down to a limited number of species does little for biodiversity.
THE PAST INFORMING THE FUTURE
In the UK and US, designers like Nigel Dunnett, Claudia West, James Hitchmough and Thomas Rainer all advocate for a form of ‘enhanced nature’. Going even further, Nigel uses the term ‘future nature’. “Instead of looking backwards to some pre-development or pristine pre-interference mode, we look forwards,” he says.
“We create natural systems that are going to work for us in the future, (instead of) two or three hundred years ago.”
Claudia says that we need to stop looking at plants as individual art objects. “In our approach, plants are living beings. They have a behaviour. They interact with other plants and their surroundings, including wildlife,” she says.
“Instead of forcing plants (into a design), we allow a certain amount of dynamic behaviour within set frames that preserve the legibility and emotional content of planting.”
PLANTING INSPIRED BY NATURE, NOT RECREATING IT
As designers, we get overly focused on planting’s functional aspects, like screening ability or low-water tolerance. Or we try to recreate long-lost ecosystems. This can make us forget the power and everyday experience of plants – the beauty of slowing down and watching a bee on a flower.
By calling for landscapes that are dynamic and in constant flux, designers are rejecting the idea that a landscape is complete on the day it’s installed, then mown, clipped, mulched, weeded and watered to maintain this stasis. Instead, we should create urban landscapes that are encouraged to grow, are resilient to change and dare I say, gardened.
IN FAVOUR OF BEAUTY
Because the pursuit of beauty is also a valid objective, though Nigel suggests that this idea has its critics. “Because you’re doing something that gives pleasure or that’s visual as much as anything else, it’s not seen as valid,” he says.
“It’s something I’ve come across a lot. If you’re making something that claims to be ecological, but you’re doing it primarily for the visual senses and for enjoyment, then somehow it can’t be doing its job, because it’s all about aesthetics.”
But surely, if we don’t celebrate the beauty of urban planting alongside its pragmatic and environmental benefits, we can’t expect the public to advocate and care for the urban environment.
THE FUTURE OF PUBLIC PLANTING
In Australia, Melbourne’s Woody Meadow project explores many of these themes. A collaboration between the University of Melbourne, City of Melbourne, University of Sheffield (UK) and Royal Botanical Gardens Victoria, the project is part of the city’s effort to re-evaluate its public planting.
A dynamic use of native plants delivers ‘enhanced community engagement with plants and public landscapes’, as well as increased biodiversity habitat, climate change resilience, and plant cover to reduce stormwater runoff and urban heat island effect. And stunning test plots show how our urban landscapes could be in the future.
This includes lasting floral plants that can be managed every two to four years, layered to reflect nature – a base of forbs and groundcovers, a ‘bump’ layer of smaller shrubs and an ‘emergent’ layer. The plants aren’t selected based on origin, although in this case all are native to Australia.
QUANTITY OR DIVERSITY?
Ultimately, the question is whether the greatest biodiversity benefits come from plant quantity, or species variety and complexity of planting arrangements?
Research suggests that it’s not only quantity but the quality and variety of vegetation that improves both biodiversity and human wellbeing.
Our public spaces must therefore be more than just ‘green spaces’. Clipped and mown monocultures must be replaced with varied, natural and complex planting. And the ‘in-between’ places - streets, gardens and even industrial areas - should all play a role in urban biodiversity. Let’s create connections to planting that will make people happier and healthier.
Improving biodiversity in our public spaces will require change to decades’ old practices in nurseries, maintenance regimes and planting design education. But the long-term benefits will bring a new, biodiverse, beautiful and complex dimension to our cities’ open spaces. It’s worth it.