The Cape Region occupies a small area on the southwestern tip of Africa. This landscape has ancient mountain ranges that have weathered over millions of years into acidic sandy soils that are low in nutrients critical to most plants. The Cape Region is renowned for a showy and diverse flora unlike that of any other area of the world. The characteristic vegetation is fynbos, an evergreen shrubland dominated by the family Proteaceae and a diverse assemblage of small-leaved shrubs. A second important community is renosterveld, a low shrubland which occurs on richer soils. Herbaceous geophytes (i.e. plants with bulbs, tubers, or other fleshy underground organs) are a notable plant group in both communities. Woodland and forest communities are rare.
These formerly high mountains have eroded over the past 200 million years into low ranges capped by resistant Table Mountain sandstone. Separating the mountains are gentle valleys and undulating plains largely underlain by shales with greater nutrient availability. Relatively young Tertiary and Quaternary limestones and sands mantle extensive areas of the coast.
The characteristic vegetation of the Cape Region, particularly on nutrient-poor quartzite soils, is fynbos. Fynbos is an evergreen shrubland dominated by four major plant morphological groups. These include two shrub groups (the proteoids and ericoids), a sedge-like group (restioids), and geophytes. The proteoids, formed by woody Proteaceae, form the tallest matrix of the fynbos community and commonly reach to 2–4 m in height. The ericoid group gains its name from the Ericaceae, but includes more than 3000 species of small-leaved shrubs from many families. The restioids are primarily members of the Restionaceae, a family with origins in Gondwanaland but which diversifiied in fynbos. Finally, the Cape Region contains the highest diversity of bulbs and other geophytes in the world, with more than 1,500 species. Many types of fynbos have been described, but a simple classification scheme includes proteoid fynbos, ericaceous fynbos, restioid fynbos, asteraceous fynbos, and grassy fynbos.
Another important vegetation type of the Cape Region is renosterveld, a low shrubland occurring on richer soils originating from shale parent material. It is floristically differentiated from fynbos by the absence of restioids and the minor importance of proteoids. This community once covered more than a quarter of the Cape Region, but has now largely been cleared for agriculture and urban expansion.
Woodland and forest communities are surprisingly rare in the Cape Region. True forests occupy only about 3,850 square kilometers of moist sites (800–1,200 mm annual rainfall) along the southern coast that are relatively protected from fire. These forests are low in diversity and represent depauperate outliers of afro-montane forests of tropical East Africa.