A deciduous shrub 2 to 3 ft high, with angular, glabrous young shoots. Leaves ovate to ovate-oblong, pointed, heart-shaped, rounded or tapered at the base, very finely toothed, 1 to 21⁄4 in. long, 1⁄2 to 11⁄4 in. wide, glabrous, very shortly stalked. Flowers solitary in the leaf-axils, each borne in June and July on a very slender stalk 1⁄2 to 3⁄4 in. long. Corolla pink, deeply divided into four narrow lobes which are curled back so as to leave 3⁄8 in. of the long anthers exposed and clustered together in a sort of column; calyx with triangular lobes. Fruits globose, 1⁄4 in. wide, bright red, pendulous.
Native of Japan and Korea; introduced about 1893. It belongs to the same section of Vaccinium as the American V. erythrocarpum, and with it forms a connecting link with the cranberries (Oxycoccus). Both have the shrubby habit of Vaccinium but the corolla is deeply split as in Oxycoccus, the lobes similarly recurved.
var. sinicum (Nakai) Rehd. Oxycoccoides japonica var. sinica Nakai – This Chinese variety has proportionately narrower leaves with down on the midrib beneath. Introduced by Wilson in 1907. V. erythrocarpum differs from both species and this variety in its downy shoots and more downy leaves; the flower-stalks are all very slender.