This paper is a first attempt to describe the flora of domestic gardens from an urban environment in South Africa. A total of 835 plant species of 501 genera in 145 families was recorded from 100 gardens in a 54.9 km2 area of the Tlokwe City Municipality [Potchefstroom], North-West Province. A substantial number of alien species (580) were recorded, but also many indigenous species (255) that included South African endemics (61) and protected species on the National Red Data List (18). A number of the alien species that were commonly cultivated are declared invasive plants in South Africa (88). Most of the cultivated indigenous taxa originated from the southeastern provinces of South Africa. This study provides new knowledge on the often overlooked biodiversity of urban areas in a developing, mega-diverse country. Most studies of a similar nature were conducted in the developed countries of Europe and are of limited use in the development of management plans of urban ecosystems in southern Africa.

In recent years domestic gardens in urban areas have been extensively studied, but findings from developed and developing countries do not always correspond. The disparity is ascribed to differences in climate, culture and socio-economics. This study from South Africa analyzes plant diversity patterns along a steep, indirect socio-economic gradient in a single city. The segregation laws of the apartheid era are responsible for the prevailing social and cultural heterogeneity. By combining cultural and socioeconomic variables into classes, the plant diversity turnover along a socio-economic gradient could be determined. This study provides further evidence of the effects that socio-economic factors, other than ecological factors which are traditionally investigated, have on vegetation patterns. Socioeconomic and cultural influences within the study area influenced plant diversity patterns, showing higher species richness in the more affluent, white-dominated suburbs. However, much of this plant diversity of affluent suburbs is made up of alien species, whereas utilitarian plants, for instance, are strongly associated with the lower socio-economic status of black suburbs, which includes many indigenous species.