Research finds majority of residential Adelaide blocks have enough space to grow vegetables for self-sufficiency

Most Adelaide residential blocks have the space to grow enough vegetables to feed the people living there, according to Adelaide Uni research.

The average Adelaide family need only give up less than a quarter of its lawn to grow enough vegetables to become self-sufficient, University of Adelaide research shows.

But households and policymakers are being warned they’re running out of time to make the change before big backyards are squeezed out of the suburbs by urban infill.

PhD candidate Isobel Hume said she was “really surprised” by the findings.

“People really can have their lawn and eat, too,” she said.

Her research showed the vast majority of the residential blocks in the study could be used to grow “five serves a day” of vegetables for 2.5 people.

“Of the 40,000 properties we looked at, 93 per cent of yards had enough lawn space alone to be self-sufficient in vegetable production,” Ms Hume said.

“This means it would not encroach on other land uses like driveways or trees, which are important for shade and biodiversity.

“Most households would only need to convert around one quarter of their lawn space to vegetable production in order to be self-sufficient.”

Veggie patch

However, she noted the area of potentially productive land had decreased over time and that trend was likely to continue, unless there was a change in government policy or regulation.

Ms Hume said Adelaide was a good case study because it was a low-density city with about 400 people per square kilometre, on productive agricultural land, with a high proportion of freestanding houses. Aerial photography was used to analyse properties at three sites: Aldinga in the south, Gawler in the north and Burnside in the east.

Previous research on the potential yield was then fed into computer models to work out whether there was enough lawn area to grow a sufficient vegetable supply.

The high-yield scenario of 16.07kg per square metre per year was considered achievable. That would required just 21sq m of growing space.

Ms Hume said urban agriculture often achieved higher yields than commercial agriculture because crops were tended by hand and “you can plant things really close together”.

The research is published in the journal Sustainable Cities and Society.

Project leader and Professor of soil ecology Tim Cavagnaro said societies had relied on urban farming during times of stress, such as the two world wars and the COVID-19 pandemic, so we should take care to preserve some land in the urban boundary for food production.

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