Jue Ming Zi is grown as an annual and is found in the China countryside along roadsides, on mountains, and aside riverbanks. It is considered a weed in many places and grows easily in almost any soil with good drainage. Though it prefers full sun it will also do well in part shade. It flowers in May to June and forms seeds in late summer.

The plant is easily propagated by seed and will spread by self-sowing if left unattended in the garden. For cultivation, seed can be planted directly in the garden in early spring. Germination is helped by scarifying the seed then pre-soaking for 2-3 hours in warm water. Seeds germinate in 1-12 weeks and in colder regions it is best to start them in a greenhouse and transplant seedlings after the last frost.

Seed are harvested in September to November after they have ripened. The whole plant is cut and dried in the sun. The seed is easily separated once the pods have dried thoroughly. For medicinal use, good quality Jue Ming Zi consists of seeds that are dry, brown and glossy.

There has been some confusion over identification of the original source plant for Jue Ming Zi. For a long time it was thought to be Cassia tora, but in 1977 when the Chinese Pharmacopeia was revised, researchers discovered that it was actually Cassia obtusifolia. Cassia obtusifolia has larger seeds and is known as big Jue Ming Zi (Da Jue Ming Zi). It is a close relative to Cassia tora, which has small seeds and is known as small Jue Ming Zi (Xiao Jue Ming Zi). Both are acceptable species for medicinal use. Cassia is ancient Greek term indicating an aromatic plant. The Latin word obtusifolia means “obtuse leaved” and refers to the leaf shape.