A strong, vigorous climber, growing 30 to 40 ft high, young stems twining, armed with a pair of spines at each bud in a young state, almost obsolete later; pith solid. Leaves shallow-toothed, 2 to 5 in. long, variable in shape, but usually either obovate or nearly orbicular; with a long, slender apex, or a short, abrupt one, narrowing at the base to a stalk 1⁄4 to 1 in. long. Flowers two to four together in small axillary cymes 1⁄2 in. long, each flower 1⁄/6 in. across, green. The fruit is at first a green, pea-shaped, three-valved capsule; but when mature the valves open and turn back, revealing their golden-yellow inner surface and the shining scarlet-coated seeds within. Bot. Mag., t. 9394.
This beautiful climber is widely spread over N.E. Asia, and seeds were first sent to Kew by Prof. Sargent in 1870 and by Dr Bretschneider from Peking in 1883. But the species is by no means so well known as it ought to be, for it is the most striking of all hardy climbers during November, December, and January. At that season each branch is furnished from end to end with hundreds of the brilliantly coloured fruits, which remain for at least two months in full beauty, each branch a wreath of gold and scarlet. Fortunately, the fruits appear to have no attractions for birds. The species is perfectly hardy, and planted in good loam soon makes a fine growth. It may be grown over a pyramid of rough oak branches, or better still, on some decrepit deciduous tree. Once attached to any support round which its stems can twine, it soon makes good its hold. C. orbiculatus is said to be completely dioecious in the wild state, but hermaphrodite clones are in commerce. A plant raised from seed may prove to be either wholly male and hence of no value except as a pollinator; or, if female, will not bear fruit without a partner of the opposite sex.
The name Celastrus articulatus, so long used for this species, was the result of a printing error on p. 97 of Thunberg's Flora Japonica, and C. orbiculatus, which appears on p. xlii of that work, is the correct name.
From the Supplement (Vol. V)
† C. gemmatus Loes. – This is near to C. orbiculatus, but with firmer, more reticulate leaves and larger, conical winter-buds, which are about 3⁄8 in. long. Native of southern and western China; introduced by Wilson to the Arnold Arboretum, Massachusetts, in 1907, but the present plants at Kew are of recent introduction.
† C. kusanoi Hayata – This is very near to C. orbiculatus, one character separating them according to Hou being that the filaments of the stamens are downy in C. kusanoi, glabrous in the other. Introduced to Kew in 1975.
Plants are also in cultivation under the name C. strigillosus, but this is usually included in C. orbiculatus.