From the November 2009 issue of the Study Group Newsletter.
This biennial conference, organized by Warwick Forge and John Patrick, is always interesting with its mix of overseas and home-grown speakers. This year there were only two of the latter. First, Stephanie Alexander told of the inspiring work she and her Foundation are doing with primary school children as they learn to enjoy growing, cooking and eating their own food (especially vegetables and herbs). In these days of obese children, it's an excellent movement that's slowly gaining ground. Later, Josh Byrne of 'Gardening Australia' spoke on integrated water systems for sustainable urban landscapes, the topic he is currently working on for his Ph.D. His facts and figures were most impressive as he compared in great detail the water savings gained at his place by the use of rainwater and grey water. To make sure no water is wasted, it's carefully metered and delivered by drip system to individual plants. Of course his soil is very sandy and well-drained, unlike the clay we have here in Melbourne. Also in his small garden there are no established trees or large shrubs, which make maintenance of ground water something I think we need to consider. I like the term 'hydrozoning' for putting plants of similar water requirements together in the garden.
The following are my personal brief responses to the overseas speakers and of course do not do them justice. Nearly all their work involved large gardens on which very large amounts of money were spent. Rosemary Alexander from the U.K. and Nancy Power from the U.S.A. both gave impressive presentations. Rosemary's gardens were very formal and constrained - she believed in "working to the grid" - photogenic but ultimately nothing new. She said "Clients feel safe with classical gardens". (I did like her recommendation for wide, shallow steps - 4 inches (10 cm) by 18 inches (45 cm) with an overhang to give a shadow.) Nancy's numerous gardens were more varied, including Mediterranean gardens with citrus trees and water. Her own was quite small. She did praise a Leptospermum laevigatum hedge and I also liked her dry humour - "Roses don't have good legs".
However I felt I really gained little new insight from their talks. Both were generally focussed on deciduous trees and/or a palette of soft-leaved plants that would have no hope of surviving now in southern Australia. The gardens they showed generally had a lush look, unattainable in a water-strapped climate, and used a range of plants quite inappropriate for an Australian "sense of place". Northern Australia has a very different climate but here I think our wonderful tropical plants are far more suitable than European annuals or soft shrubs and they also give their own special 'look'.
Two French landscape designers spoke separately about the gardens they have designed together. Eric Ossart described and showed their gardens in Morocco, where they have lived for some years. Here buildings have a plain, walled exterior while inside there may be a beautiful courtyard garden. They're the typical gardens of desert areas, always with some water. Arnaud Maurieres illustrated their very different gardens in France. He said that while country gardens must link to the landscape, for urban gardens "there is no landscape". Also around the same building there are many microclimates, so many different gardens exist within the one garden.
Marta Montero spoke about South American artist and designer Roberto Burle Marx and 'the lyrical landscape' including the use of curved beds, massed planting and colour. Looking more to the future, I did enjoy hearing from Edmund Snodgrass about roof gardens and seeing the numerous examples he showed. He talked about the ecosystem services provided by roof gardens and explained in some detail the structural support required for them. Six distinct layers are required, though some of these can be combined in certain materials. In brief, the taller the plants grown, the heavier the sub-structure needed. Plants can go from low succulents and grasses to shrubs and even trees. Edmund talked about the use of native plants, self-sowing plants and seasonality in roof gardens. The aim is for 'low imports' of both water and nutrients.
Australia now has a few green roofs but Europe (especially Germany and Norway), Canada and America are way ahead of us. In Stuttgart, for example, roof gardens are mandated for any flat roof. I hadn't realized they can be grown on slopes of up to 45 degrees. There's an enormous amount of information out there (just google 'greenroofs' to see). I hope we'll have an increasing number of green roofs here, especially in our cities to help reduce the heat island effect. It's claimed the temperature of Chicago has been lowered 7 degrees by greening roofs.
The highlight of the conference for me was hearing Thomas Woltz, an enthusiastic American involved in designing a great number of landscapes, some on a very large scale. He talked about being consistent in your approach to a project - "following your own story". In his first talk he described how he persuaded councils and/or developers to let him 'daylight' streams that had been confined in underground pipes for many years, in order to create attractive waterways through urban (or suburban) development projects.
Thomas uses local plants where possible for connection to place. Some of his work is similar to revegetation projects but he deliberately designs with local plants rather than using them in a more natural way. In New Zealand he is part of a team working on the design of a very large coastal property which is a farm but also serves as an example of 'conservation agriculture'. One complete headland has an exclosure fence to keep out feral animals, so sea birds can nest there safely. He talked about developing strategies for biodiversity. To measure their success, specialists in many fields have carried out studies of the wildlife as a 'baseline for biodiversity', so progress can be studied over the years ahead. He also uses 'eyes', small devices to measure and record over a two-year period the temperature of the air and water at selected places. He consulted the local Maori people to get their input to the project. This short description does not reflect the range of his work, which I thought was inspiring.