Australia: Green roof opportunities for nurseries
When Darren Mason, now sales director for Andreasens Green wholesale nurseries, started his nursery career in 1983, his first major project was to grow and deliver plant material for the podium rooftop garden on top of Parliament House in Sydney.
He says people forget the concept has been around that long, and believes it is finally gaining momentum, as city councils begin to mandate that new buildings have green roofs and evidence emerges of their benefits for residents and workers.
Darren Mason, Andreasens Green
“The nursery industry really needs to position itself as a research partner in trials with universities and government agencies, to determine which plant species and growing media suit different sites and climates across Australia,” Mr Mason said.
“To maximise our potential involvement, we need information readily available on the types of materials to supply for green roofs, particularly the areas we can specialise in such as plant species, growing media, fertiliser and water proofing.
“Pretty much anything goes at the moment in green roofs, depending on the depth of the growing media, site orientation, purpose of planting, council guidelines and client requests, but we need evidence of how this differs from site to site.”
Mr Mason was encouraged to see Burwood Council, in Sydney’s inner west, make green roofs mandatory in new residential buildings late last year.
Around 2600 dwellings are expected to be built over the next five years, with all new developments required to have at least 50 per cent of their roof area filled with grass, shrubs or trees.
An example of a green roof. Image supplied by Andreasens Green.
“It’s easier to put a green roof on a new building rather than retrofit an older building, but all the rooftop areas are just wasted space, so why not put a green roof on?” Mr Mason said.
“They promote the green roofs concept better overseas, where populations are so much larger and there’s more scope.
“I believe areas of Germany have up to 40 per cent of buildings covered in rooftop gardens, and I think in the next five years we will see a major increase here in Australia.”
Australia does not have a national policy on green roofs and green walls, and research* is now underway to explore the pros and cons of a mandatory approach to planning legislation, versus the current approach where most councils simply ‘encourage’ their use.
The benefits of green roofs are not just aesthetic, with research** showing they can provide psychological restoration for office workers, lifting their mood and overall performance.
The study, which quantified the benefits to workers from looking onto a green roof rather than a concrete structure, found even limited exposure to green roofs through micro-breaks at work was associated with reduced stress and improved health and wellbeing.
One Central Park, Sydney. Image supplied by Andreasens Green
Mr Mason’s employer, Andreasens Green, is a sponsor of Green Roofs Australasia, a body set up to promote the benefits of green roofs in mitigating the effects of climate variability in cities, such as an increase in urban flooding and rising temperatures from hard roof areas.
He says it’s also critical that urban planners prevent the loss of fauana such as birds and bees from the inner city, through the creation of a roofscape of green across the city.
“By linking up these precincts with green roofs, we promote greater biodiversity and provide cleaner air, water retention rather than runoff, and a connection with nature rather than concrete,” he said.
* Expanding the living architecture industry in Australia (GC15001), part of Horticulture Innovation Australia’s Green Cities Fund, and co-funded by University of Technology Sydney, Aspect Studios, Fytogreen, Elmich Australia and Junglefy.
** Part funded through Increasing productivity through industry research, development and extension program’ (NY13003) funded by Horticulture Innovation Australia Limited using the nursery R&D levy and funds from the Australian Government.
For more information:
Nursery & Garden Industry Australia
info@ngia.com.au
www.ngia.com.au