Oriental Bittersweet
Celastrus orbiculatus

Family: Celastraceae

What it is like

Celastrus orbiculatus is a deciduous Climber growing to 12 m (39ft) by 12 m (39ft) at a fast rate. See above for USDA hardiness. It is hardy to UK zone 4. It is in flower from July to August, and the seeds ripen from November to February. The species is dioecious (individual flowers are either male or female, but only one sex is to be found on any one plant so both male and female plants must be grown if seed is required). and is pollinated by Bees. Suitable for: light (sandy) and medium (loamy) soils, prefers well-drained soil and can grow in nutritionally poor soil. Suitable pH: mildly acid and neutral soils. It can grow in full shade (deep woodland) semi-shade (light woodland) or no shade. It prefers moist soil.

Height (m): 12

Where it is found

Thickets on grassy slopes in lowland and mountains all over Japan. Forest edges in China.

N.E. Asia - China, Japan, Korea.

Conservation Status: This taxon has not yet been assessed.

Countries/locations it is found in

Asia: China, Japan, Korea, Mongolia, Taiwan, USA, Europe: Russia, UK, Oceania: Australia, New Zealand.

How it is used

Food

Rating: 1

Young leaves - cooked.

Medicine

Rating: 2

The roots, stems and leaves are antiphlogistic, antirheumatic, depurative and tonic. A decoction of the roots and stems is used internally whilst the crushed fresh leaves are used for external applications. The plant is used in the treatment of paralysis, numbness of the four extremities, headache, toothache, spontaneous abscess formation and snake bites. Many plants in this genus contain compounds of interest for their antitumour activity.

Antiphlogistic: Reduces inflammation.

Antirheumatic: Treats rheumatism.

Cancer: Used in the treatment of cancer.

Depurative: Eliminates toxins and purifies the system, especially the blood.

Tonic: Improves general health. Slower acting than a stimulant, it brings steady improvement.

Other

Rating: 1

Used as a hedge. Ornamental.

Hedge: Plants that can be grown as hedges.

Hedge: Hedge

How it is grown

Prefers a deep loamy soil but succeeds in most soils so long as they are not too shallow. Succeeds in full or partial shade. Plants flower more freely if their top-growth is in the sun. Requires a humus-rich soil if it is to be at its best. A very ornamental plant, it is hardy to about -25°c. A rampant climber, it requires ample space and is best grown into an old tree. It climbs by means of twining and also by the young stems having prickles. Plants do not normally require pruning. Plants in this genus are notably resistant to honey fungus. Plants are usually dioecious, in which case male and female plants must be grown if seed is required, but hermaphrodite forms are in cultivation.

Propagating it: Seed - gather when ripe, store in dry sand and sow February in a warm greenhouse. Three months cold stratification leads to a higher germination rate. Remove the flesh of the fruit since this inhibits germination. Germination rates are usually good. When they are large enough to handle, prick the seedlings out into individual pots and grow them on in a greenhouse for at least their first winter. Plant them out into their permanent positions in late spring or early summer, after the last expected frosts. Cuttings of half-ripe wood, July/August in a frame. Layering in August of the current seasons growth. Takes 12 months. Root cuttings, 6mm thick 25mm long in December. Plant horizontally in pots in a frame.

Best place to grow: Woodland Garden Dappled Shade; Shady Edge; not Deep Shade; Hedge;

Habit: Climber

Hardiness: 4-8

Growth: Fast

Soil: Light (sandy), medium

Shade: Full shade, semi-shade, no shade

Moisture: Moist

Things to keep in mind

Considered to be an invasive species in eastern North America. As a fast growing, twining vine, C. orbiculatus is a threat to other plants through constriction of the woody stems it climbs upon leading to slowed growth and eventually mechanical failure, over-topping and shading out plants beneath it, and outright competition for resources.

Its other names

Local names

Preferred Common Name: Asiatic bittersweet. Other English: Asian bittersweet; Chinese bittersweet; Japanese bittersweet; oriental bittersweet. Germany: Baumwürger, Rundblättriger. Japan: tsuru-ume-mo-doki. New Zealand: climbing spindleberry. USA: round-leaved bittersweet. Others: Baiwanye, Man she teng, Nobaktonggul.

Synonyms

C. articulatus. Thunb.