Callerya speciosa Seeds | Showy Callerya
LATIN NAME: Callerya speciosa
COMMON NAME: Showy Callerya
Plant Profile
Showy callerya is a climbing legume with two lives. Above ground it is a vigorous twiner with pinnate leaves and pea flowers in loose, lilac-purple racemes, pretty enough to grow over a pergola in a warm garden. Below ground it makes a thick, pale, starchy tuber, and that tuber is the reason the plant is cultivated across southern China, where it is sold as niu da li and used in soups and tonic preparations. The vine climbs three to five metres, twining clockwise, with a woody base that thickens with age. It comes from the hill forests of Guangdong, Guangxi, Hainan and northern Vietnam, on acid soils in warm, humid country. The name speciosa refers to the showy flower, and the ornamental value is real, but the root is the crop. It flowers in summer and sets flat, hairy pods in autumn.
Science & Biotechnology
Callerya speciosa was long placed in Millettia, and it was moved to Callerya on the basis of molecular and floral characters; the two genera sit in the tribe Millettieae, which is one of the legume groups where nodulation is patchy and has been lost and regained several times. The plant’s economic organ is a tuberous root that stores starch and water, and it develops slowly over several years, which is why cultivated material is harvested at three to five years rather than annually. The root is rich in polysaccharides and in flavonoids, and it is one of the ingredients of the tonic soups of Guangdong and Guangxi, where it is regarded as a lung and kidney tonic. As with most Millettieae, the seed has a hard, water-impermeable coat, and germination in the field depends on abrasion or fire. The flowers are pollinated by bees and are visited by carpenter bees.
Uses & Benefits
The root is the main use: sliced and dried, it goes into slow-cooked soups with pork or chicken, and into commercial tonic preparations sold across southern China and in Chinese pharmacies abroad. It has a mild, sweet, starchy flavour and is treated as a food-grade tonic rather than a drug. The vine is also a garden ornamental in warm climates, grown on a strong pergola for the summer flowers and the dense screen of foliage. In its native range it is a component of secondary forest and a nitrogen fixer, and it is used in intercropping on acid hill soils. The stems are used for rough cordage locally. Anyone using the root medicinally should buy from a reputable source, since wild collection has increased and cultivated material is now the better choice.
Growing from Seed
Scarify the seed by nicking the coat with a file or sandpaper, then soak it in warm water for twelve hours; sow into a gritty, well-drained mix at 22 to 28 degrees and expect germination in two to five weeks. The seedling needs a stake or a string from the first month, because the shoot will hunt for support and sprawl if it finds none. Grow it in a deep pot for the first two years so the taproot can develop, and use a mix with plenty of organic matter and sharp drainage. Plant out in a warm, sheltered, sunny position in acid soil, and water through the first two summers. The top growth may die back in a cold winter and resprout from the tuber in spring. Harvest roots at three to five years, and leave the crown to regrow.
Our Take
A dual-purpose vine for warm climates: lilac flowers on the pergola and a starchy root for the soup pot. Give it a strong support and a deep pot at first.
Related Reading
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