Soils: A gardener’s guide to the Ecovillage

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If you’re seriously considering living in the Witchcliffe Ecovillage, it’s probably safe to assume you have a green thumb, or at least, that you’re interested in eating organic, nutritious, fresh produce. And as all gardeners and permaculturalists know, the building block for growing healthy food is healthy soils.

Growing conditions and soils in Western Australia can vary significantly. The deep, poor sands of the coastal plain are easy to dig but require frequent water and ample organic matter to build up soil structure. The heavy clays and rocky soils of the Perth Hills present their own challenges and opportunities.

Our site at the Witchcliffe Ecovillage is different again, and if you don’t hail from the Augusta Margaret River region, you may well be unfamiliar with the soils, rainfall and climate here. So, we wanted to dig a little deeper and give you an idea of what to expect when you start gardening here.

A quick history of the site

The 120ha (300 acre) Witchcliffe Ecovillage site was previously occupied by two farms: an organic vineyard to the south and a dairy farm to the north. Prior to that, they were originally group settlement farms, owned and farmed for many years by the Fox family, (hence the vineyard’s name, ‘Foxcliffe’.)

More recently, Cape Mentelle owned and managed the Foxcliffe vineyard organically and, it’s been said, produced some of the best Cabernet Sauvignon grapes in the region from its beautiful soils. Likewise, the former dairy farm produced mainly cream (not milk) so rich were its lush, green pastures.

Our soils clearly have a fine gardening pedigree. The terroir that imbues some of Margaret River’s finest Cab Sav will be a fantastic starting point for growing nutritious, tasty, organic vegies, while also continuing to support a small red grape vineyard block for the production of Ecovillage wine.

Ecovillage soils

The Ecovillage site is largely flat with a gently rolling topography of cleared paddocks. The soils are primarily sandy loams, 0.5m to 1m deep, with some areas of gravelly loams and some isolated laterite outcrops. The upper soil layers are generally free-draining with a low permeability clay layer underneath.

The underlying clay layer has advantages and disadvantages. Once trees get their roots down into the soil, they have easy access to soils that retain moisture and provide good spring and summer growing conditions. However, this means that soils in flatter areas of the site retain water for longer periods in winter.

With that in mind, we have developed a sophisticated drainage strategy with a greater level of stormwater and groundwater water management for residential development. The rain garden system will be an integral part of every community garden cluster and will minimise the adverse effects of major rain events and waterlogging. It also means we need to restrict construction activities to summer to minimise impacts on the site.

The laterite outcrops on farms in the region (usually orange gravel and ironstone areas) were typically seen as not suitable for pasture and were often left uncleared. This practice was followed by the Fox family, which has left such remnant patches of forest in cleared areas.

As a result, there is a healthy stand of jarrah and marri trees on the central eastern side of the site that we have retained in a conservation area that will be managed by the community. Similarly, there are gravelly soils in the south eastern corner of the site where the vineyard has been retained, which are perfect for its premium quality cabernet vines.

Dam construction began in February 2019 and revealed an ochre rainbow of white, cream, yellow, orange, brown and rusty red. There is plenty of water repellent clay with which to line the dams, as well as pockets of gravel, which we have stockpiled for use on the paths and cycleways that will crisscross the Ecovillage. Excess clay and soil from the dam construction is being used to form berms (raised embankments) along the highway to dampen noise and create a visual barrier to the development. These will be planted out with a variety of natives to stabilise the soil and create a green wall. A linear olive grove will be planted along the base of the berm, which will eventually provide us with Ecovillage olive oil.

Soil testing

Our soils have shown they are ideal for viticulture and pasture, but to ensure their suitability for horticulture, we have undertaken extensive soil testing across the site during the last few years. This helps us understand the mineral levels and organic matter content. Essentially, it guides us in developing balanced, productive soils. And the good news is they are in great shape and generally require very little amelioration. That said, after years of agriculture, unsurprisingly, the levels of organic matter in the soil have been depleted. So, adding plenty of compost, mulch and cycling green manures will help build humus levels and promote a healthy soil food web.

Organic management

The vineyard has been managed organically since it was established in 1998, and since we purchased it in 2010. However, it wasn’t certified organic. So, it is now certified “in conversion” by NASAA, as are the office demonstration vegetable gardens. The entire Ecovillage will be managed organically, although, for practical reasons, only the agriculture lots and vineyard will remain in certification. Key documents including the Community Garden Handbook, Strata By-Laws and the Building Design Guidelines will provide guidance to Ecovillage residents on how to work within this system. In addition to a wealth of inherent knowledge in the community, residents will be able to draw on the services of several permaculture and horticulture experts within our team that intimately understand the site and Ecovillage requirements.

Our team

Horticulturalist, Mark Tupman, is the latest addition to the Sustainable Settlements team and joins PB Foreman and Paul Jurejevich in the gardens and vineyard. Mark is currently working one day a week with us, but will be coming on full-time mid-year to manage the expansion of the office demonstration gardens and the development of the horticulture program for the Ecovillage. Mark has spent the last 15 years teaching horticulture at Denmark TAFE from the certified organic market garden, and most recently teaching horticulture at Bunbury TAFE. Mark has a wealth of knowledge about establishing and running highly productive organic gardens and we are absolutely thrilled that he has joined our team.