Australian 'Bush Potato'

Dr Adam Marchant - Senior Technical Officer

Ipomoea costata is a species in the family Convolvulaceae, which is endemic to the arid tropics of Australia, being found from Queensland, across the Northern Territory and northern Western Australia. Its tuber, a ‘bush potato’, was one of the important food sources of the indigenous people in these areas. I. costata is in the same genus as the sweetpotato, which was domesticated in Central America from the wild species I. trifida, and is now rated as the seventh most important food-plant worldwide.

Our project - generously funded by the Australia and Pacific Research Foundation - is an investigation into the horticultural potential of the Australian Bush Potato. We have been studying its distribution range and abundance, in comparison to historical records, and making collections for growing trials as well as botanical and genetic studies. Experimental plantations from material that we have collected are now growing in Broome and Bidyadangar, on the northern coast of Western Australia, where it joins other traditional food plants in the community garden.

Very few of the foods used by indigenous Australians in pre-European times have been adapted to production for modern consumption, and of those which have, most are condiments, and treated as curiosities. Conversely, the vast majority of the population of the modern world relies for its staple foods on a very small number of plant species - wheat, rice, potatoes, etc. There is a need to increase the diversity of the basic foods on which the world depends, and the unique flora of our continent should be examined with the aim of contributing to that end. Whether I. costata can be brought into commercially viable production, improved for domestication, or even contribute genetic material for the improvement of sweetpotato, remains to be seen. However, this project has already succeeded in re-introducing and making available an important component of the traditional cuisine to some of the indigenous people who no longer live on their ancestral lands.

Adam Marchant, in collaboration with George Orel (UWS), Annette Hill, Kim Courtenay (TAFE-WA Broome) and Tom Harley (Kimberley Environmental Horticulture).

Planting out at Bidyandanga community, WA - Annette Hill, Merridoo Walbidi, Adam Billycan (photo by Kim Courtenay)

John Nundi and Adam Marchant with some of the first harvest (photo George Orel)