Gaynor presents some quantitative evidence for the scale, distribution, and focus of food production. The 1941 "Melbourne University Social Survey", for example, reveals that "48% of sampled households produced food of some kind", with 6% keeping poultry for eggs, among other data that can be used to explore "linkages between poverty, space, and food production". Apart from surveys, other sources of information include regulations, advertisements, and figures for sales of fertilisers, pesticides, seeds, tools and so forth.
More of Harvest of the Suburbs, however, is devoted to the cultural and ideological background of domestic food production. Among the traditions and influences considered are Samuel Smiles and ideas of self-help, the permaculture movement, the Great Depression and poverty, the development of ecology as a science, trends in fertilisers, concerns about purity and pesticides, organic farming and integrated pest management, changes in urban planning approaches, and gentrification. One source of tension in communities and movements is the balance between ideas of independence and ideas of interdependence.
"In the mind's eye of many Australians at the end of the twentieth century, the productive backyard, with its chooks and vegies, formed part of a bygone era... But home food production in the 1990s was more common than it seemed. From the 1970s, environmental ideas combined with the impact of rolling recessions to produce an apparent 'renaissance' of productive gardening and backyard animal-keeping. In the early 1980s, vegetable seedling nurseries and seed merchants responded to an apparent increase in demand, almost trebling their output of 1976."
It's not a racy read, but it's not too dry either. There are plenty of engaging details as well as the broad overview, and Harvest of the Suburbs may appeal even to those outside Australia, or without direct involvement in gardening themselves.