Mucuna sempervirens Seeds | Evergreen Mucuna
LATIN NAME: Mucuna sempervirens
COMMON NAME: Evergreen Mucuna
Plant Profile
Evergreen Mucuna is a woody climber of the pea family, native to the evergreen broad-leaved forests of central and southern China. It can climb twenty metres into the canopy, twining around trunks with stems that thicken with age until they look like ropes. The leaves are trifoliate, glossy and held all year.
In late spring the vine hangs out pendulous racemes of dark purple, bird-shaped flowers with a faint smell of fermenting fruit, followed by velvety pods up to forty centimetres long, packed with hard, mottled seeds. An old plant can smother a small tree, so it wants a strong pergola rather than a delicate host.
Science & Biotechnology
The genus Mucuna is one of the most closely studied legume groups in seed chemistry, because its seeds carry high concentrations of L-DOPA, the direct precursor used in Parkinson’s disease therapy. M. sempervirens sits in the same clade, and Chinese pharmacognosy has examined its stems and seeds for alkaloid content, although it is not the commercial source.
Work in Yunnan and Sichuan has also tested the species as a nitrogen-fixing cover crop for orchards and tea terraces, where its fast growth suppresses weeds and its root nodules add nitrogen. Chromosome counts and molecular markers place it close to Mucuna birdwoodiana, and seed collections from wild stands are held by several provincial institutes.
Uses & Benefits
In gardens it is grown for speed and shade: a single plant will cover a pergola in two seasons, and the hanging racemes in May are unlike anything else hardy in a temperate climate. The pods are covered in irritant hairs that cause itching, so gloves are needed at seed harvest.
Stems are used in regional Chinese medicine under the name chang chun you ma teng, mainly in decoctions for joint and circulatory complaints. The pharmacology is preliminary, and the plant is not a substitute for prescribed L-DOPA therapy. Livestock poisoning from pods has been reported in cattle, which is worth knowing if the vine borders a field.
Growing from Seed
Fresh seed germinates fast. Nick the hard coat with a file or soak it in warm water for a day, then sow two centimetres deep in a free-draining mix at 20-25C. Seedlings are vigorous and need a tall support within weeks; a bamboo cane in a three-litre pot is quickly outgrown.
Give full sun and steady water in the first season, and plant out after the last frost against a warm wall. The vine is hardy to about -10C once the root is established, though top growth may be cut in a hard winter and will resprout from the base in spring.
Our Take
Not a plant for a small garden, and not one to leave unsupervised beside a favourite tree. Grown on a strong frame in a sheltered corner, though, it gives a fast, exotic canopy and a flower display that few hardy climbers can match.
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