A deciduous climber, up to 20 ft high, with twining stems. Leaves very variable in shape, perhaps normally ovate-cordate and entire, but sometimes almost kidney-shaped, sometimes lobed like Catalpa ovata, sometimes deeply three- or five-lobed (with lanceolate lobes), sometimes shallowly so; often with a lobe on one side only; the base often truncate; 2 to 6 in. long, 11⁄4 to 41⁄2 in. wide; deep bright green, glabrous, with three or five conspicuous veins radiating from the base; stalk slender, 2 to 6 in. long. Flowers small, yellow, unisexual, about 1⁄6 in. wide; sepals six, in two series of three each, downy beneath; petals very small; the flowers are borne in slenderly pyramidal panicles 6 to 12 in. long, the main and secondary flower-stalks downy. Fruit about the size of a small pea, globose, black, covered with blue bloom.
Native of E. Asia. Although described by Thunberg in 1784 from a Japanese plant, it does not appear to have been introduced to cultivation until Wilson sent seeds from China to Veitch’s Coombe Wood nursery in 1901. It is perfectly hardy, and a vigorous grower.
var. cinereum (Diels) Rehd. & Wils. Cocculus diversifolius var. cinereus Diels – Leaves downy above, densely so beneath. Introduced by Wilson in 1907 from W. Hupeh, where, as in W. Szechwan, it is commoner than the glabrous type. Some of the plants raised from Wilson’s 1901 seed may have belonged to this variety, which seems to be the commoner in gardens also.