Clethra delavayi is treated here as a single, highly variable species. All characters that have been used to delimit more narrowly defined species in other treatments of Chinese Clethra exhibit a strongly continuous pattern of variation from west to east across the range of the species in China[]

Common Name:

General Information

Clethra delavayi is a deciduous shrub or a tree usually growing up to 5 metres tall, occasionally reaching 13 metres[].
The plant is harvested from the wild for use as a medicine. It is grown as an ornamental, valued especially for its fragrant flowers in late summer[].
Clethra delavayi has a very wide distribution, large population, is not currently experiencing any major threats and no significant future threats have been identified. The plant is classified as 'Least Concern' in the IUCN Red List of Threatened Species(2019)[].

Known Hazards

None known

Botanical References

,

Range

E. Asia - northeast India, Bhutan, southern China, Myanmar, Vietnam

Habitat

Mixed or coniferous forest margins,, more or less open thickets, slopes to alpine regions; at elevations from 300 - 4,000 metres[].

Properties

Conservation Status	Least Concern
Medicinal Rating
Habit	Deciduous Shrub
Height	5.00 m
Pollinators	Bees, Butterflies
Cultivation Status	Wild

Cultivation Details

Clethra delavayi is is not very cold-hardy, and can be damaged if temperatures fall below -10°c[].
Prefers growing in an open woodland with its roots in the shade. It requires a humus-rich, lime-free, moist but well-drained soil[].
The flowers are very fragrant[].

Edible Uses

None known

Medicinal

The root is pungent and bitter in taste, neutral in property. It promotes blood circulation and the removal of blood stasis, and strengthens the muscles and bone. A decoction of the roots is taken internally, it is often used for the treatment of injuries caused by knocks and falls; the later stage of fracture; numbness of the limbs; and weakness of the waist and knees[].
The roots are harvested in summer and autumn, sliced, and dried in the sun[].

Other Uses

None known

Propagation

Seed - sow early spring in a greenhouse[]. Only just cover the seed and keep the pot moist. Germination usually takes place within 1 - 3 months at 13°c[]. When large enough to handle, prick the seedlings out into individual pots and grow them on in the greenhouse for at least their first winter. Plant them out once they are more than 20cm tall in late spring or early summer after the last expected frosts.
Cuttings of half-ripe wood, 7 - 10cm with a heel, mid summer in a frame[, ]. Very easy[].
Root cuttings in December/January[].
Layering of current years growth in late autumn. Takes 18 months. Can also be done in early spring[].