Plants from the temperate climate zones of the Southern Hemisphere make up one of the focal points of the HHU botanical garden. The garden's first director, Professor Dr Wilfried Stubbe, laid the foundation for the collection using specimens he acquired during fieldwork in South America. He also collected rare species from South Africa. The garden's holdings have been expanding ever since. Among its most interesting plants are members of the Proteaceae, Podocarpaceae and Cycadaceae families.
The remarkable collection is exhibited in the South Africa house, which offers a suitable environment spanning 330 square metres. Its ground consists of rock and a one-metre layer of soil that was specially chosen for its nutrient profile, which closely resembles the natural habitats of the plants. The walls of the greenhouse open on two sides, exposing the plants to wind and natural sunlight. Combined with a relatively low temperature and an automatic ventilation system, this set-up provides a slight degree of environmental stress similar to that experienced in nature. It is a prerequisite for healthy growth.