A vegetation survey was conducted of the Owen Sitole College of Agriculture (OSCA). Phytosociological data were used to identify plant communities and to determine alpha diversity. Five plant communities were recognised and described. One of these was sub-divided into two sub-communities. An ordination scatter diagram of the distribution of the six vegetation units depicted topographically induced gradients, specifically related to soil depth, rock cover, slope and altitude. Floristic composition of the six vegetation units indicates that this coastal thomveld has affinities to the Grassland, Savanna and Forest biomes. In the study area, closed woodland communities have the highest plant richness and grassland communities the highest plant diversity. Diversity and richness per community compares favourable with the Rocky Highveld Grassland, suggesting that phytodiversity at OSCA was maintained despite a history of multiple disturbances. The habitat on OSCA farm serves as an important refuge for plant species and communities of biological and economic significance, especially the remaining grasslands.