An Introduction to the Characteristics of Rehmannia Root and Its Cultivation Value

Rehmannia root is the underground tuberous root of the Scrophulariaceae plant Rehmannia (Rehmannia glutinosa), and it is also the main part used as medicine; it gets its name from its yellow, lustrous color. The fresh tuberous root is thick and fleshy, with a cross-section that is yellow or yellowish-white; after drying or processing it can be made into different specifications such as raw rehmannia and prepared rehmannia. The Huai rehmannia produced in Henan and other places is especially well known.

Rehmannia prefers a warm, sunny environment, and it fears both waterlogging and continuous cropping. The best planting plots are sandy loam with deep, loose, fertile soil and good drainage; heavy clay or low-lying, waterlogged land easily causes the tuberous roots to rot, and the same plot generally needs to be rotated with other crops for several years before being planted again.

For propagation, cut-section vegetative propagation is mostly used. Planting is done after temperatures rise in spring, and after emergence attention should be paid to intertillage, weeding, and moderate topdressing. During the rainy season, drainage should be carried out in time to avoid water accumulation in the field that would suffocate the roots. During the growing period, diseases and pests such as leaf spot, wilt, and cutworms are likely to occur, so prevention should be the main approach, and timely targeted control should be carried out once they are found.

Rehmannia root is a traditional commonly used Chinese medicinal material. Its fresh use, dried use, and processed use each have different emphases in medicinal properties, and it is used in both the pharmaceutical and food-processing fields. Growers can arrange production according to local climate and market demand, and only by doing a good job in links such as site selection, planting material, and field management can they obtain better quality and returns.