Medicinal plants have been identified and used throughout human history. These plants can synthesise a wide variety of chemical compounds with different biological functions, including healing and well-being. There are many people, especially in the rural communities, who believe in the effectiveness of medicinal plants used in traditional medicine practices.
Because they are affordable and accessible, there is an increasing reliance on the use of medicinal plants to meet healthcare needs, by a growing African population. Popular medicinal plants in South Africa include cancer bush (Sutherlandia frutescens), African potato (Hypoxis hemerocallidea) and African ginger (Siphonochilus aethiopicus).
Medicinal plants are also important resources for the development of the global pharmaceutical industry. It was estimated that about a quarter of globally prescribed drugs are of plant origin. The current situation is that most medicinal plants (including the endemic ones) are extensively collected from the wild population and are often over-exploited. An growing demand for certain medicinal plants has resulted in market scarcity and critical population decline of many species in their natural habitat. Thus, the conservation or sustainable utilisation of these plants is imperative if present and future generations are to benefit from these medicinal plants.
Cultivating medicinal plants is a good way to ensure sustainable availability of plant material to meet the growing demand. However, the cultivation of high quality medicinal plants requires intensive care and management.
Medicinal plants of the same species can show a significant difference in quality when cultivated differently or at different sites. Therefore, systematic cultivation and good agricultural practices are required to ensure that the medicinal quality of cultivated species is not compromised.
Research studies conducted at the ARC Vegetable and Ornamental Plant centre (ARCVOP) on various medicinal plants focuses on improved propagation and cultivation practices, and on quality assessment of the medicinal active compounds in the plant material. Research to optimise cultivation practices includes investigations into planting density, irrigation requirements, fertiliser management (organic versus inorganic) and pruning.
Research on some high demand medicinal plants, including African potato (Hypoxis hemerocallidea), African ginger (Siphonochilus aethiopicus), Sweet wormwood (Artemisia annua), Cancer bush (Sutherlandia frutescens), Moringa (Moringa oleifera) and Rabassam or Umckaloabo (Pelargonium sidoides), has indicated that medicinal plant yield can be increased without compromising the medicinal quality of the harvested material. – ARC Newsletter