AGENDA
- Burnley Living Roofs by Hassell is a
research and demonstration garden at
the University of Melbourne’s Burnley
Campus. Photo: Simon Griffiths - A green wall designed by Patrick Blanc
at One Central Park, Sydney. The wall’s
diverse planting scheme demonstrates
the benefit of using multiple plant forms,
colours and textures for visual effect.
Photo: John Rayner
recycling or filtration, ecological effects through
biodiversity and a reflection of social values.
Researcher Leigh Staas from Sydney’s Macquarie
University highlights how a green roof or wall
becomes “truly alive” when a diversity of species are
planted to attract birds, insects and reptiles. Locating
flowering species across different building levels and
profiles strategically connects the building to nearby
street or park trees and reinforces the urban ecology.
The site analysis stage determines planting
design parameters. Designer Matthew Mackay’s (now
Aspect Studios) experience working on Hassell’s
Medibank Place in Melbourne attests to the value of
engaging with precise building and environmental
data, such as materials, wind and light. From the
outset of the project, digital information models
issued by engineers and architects allowed the land-
scape architecture team to fully engage with the
project, integrating as many green spaces as possible
through a combination of modular planter boxes,
roof gardens and green facades. A grasp of regional
climate patterns is fundamental at this stage. This
becomes all the more important at the project
procurement phase, especially when discerning
information and specifying the best possible system
for the site context. The challenge can be convincing
clients and subcontractors to substitute inferior or
untested systems.
The rapid rate of technological developments,
commercial competition and the mass of conflicting
information is overwhelming and causes confusion,
says Erik Van Zuilekom, botanist and garden designer
at Fytogreen, a specialist green infrastructure
company. Many factors need to be weighed up when
designing a planting system – this includes consider-
ing the benefits of hydroponic versus soil-based
systems and modular versus non-modular systems,
remote management of irrigation and varying insula-
tion properties. Structural considerations further
narrow the options, as with roof garden substrates
(growing media), where the composition varies
between brands and a lack of clear performance spec-
ifications makes comparisons difficult. Each system
poses other issues, such as intellectual property rights
and risks, which have all sorts of implications for the
design and management of the planting lifespan.
Planting design is an iterative and highly collab-
orative process. Aspect Studios’ Warwick Savvas has
worked extensively on the largest and technically
most complex green roof in the southern hemisphere,
on the plant site at the Victorian Desalination Project.
According to Savvas, methodical and regular
reviewing with specialists – including botanists,
horticulturalists, ecologists, engineers, architects,
material technicians and maintenance contractors –
is essential. They provide critical appraisal of the
design from the preliminary stages through to devel-
opment and design documentation. Consistent
matching of plant traits with the project performance
criteria informs the fit-for-purpose plant selections.
As high-quality information sources, the plant
specialists augment the knowledge of landscape
architects about plant growth and types. Designers
need to strike a balance between aesthetic patterns of
planting layouts and the distribution of plants based
on tolerance and exposure, and move beyond repre-
sentations of green roof meadows from Europe and
the USA.
Finally, design needs to consider the mainte-
nance and management phases of a project,
particularly clarity around what is required to sustain
the design outcomes, including plant life cycles. Apart
from the economic benefits to the client, the designer
is vested in the success of the planting. John Rayner,
director of urban horticulture at Burnley Campus, the
University of Melbourne and specialist green infra-
structure consultant, emphasizes the importance of
management feeding accurate information about
available resources and costs back to designer, so as to
inform major design decisions in the future. He cites
some current green infrastructure projects that are
reliant entirely on potable water as being at risk in
future spells of water restrictions.
There is a need for more performance data
about plant growth and environmental variables.
Technologies that integrate information, such as BIM
software, are not yet versatile enough to grapple with
living systems. Ultimately, it is incumbent on land-
scape architects to advocate planting design values
and skills, as is done in professional associations
like the American Society of Landscape Architects.
Formidable local precedents include Hassell’s Burnley
Living Roofs project, publications like Melbourne’s
Growing Green Guide, and the forthcoming interactive
online tool to be released as part of Horticultural
Innovation Australia’s “Which plant where, when and
why” project. Backed by such resources, landscape
architects in Australia can begin to more rigorously
engage with planting design in green infrastructure,
enabling them to stake a strong claim in – and add
their voice to – this demanding area of design.224 MAY 2017 LANDSCAPE ARCHITECTURE AUSTRALIA