A deciduous shrub probably 3 or 4 ft high, the erect, slender, sparsely branched shoots covered with silky hairs when young. Leaves oval to lanceolate, from 1 to 2 in. long, 1⁄3 to 5⁄8 in. wide; pointed, silky-hairy beneath, short-stalked; mostly opposite, occasionally alternate. Flowers lilac-coloured, produced during May at the joints of the naked wood of the previous year in stalked clusters, the stalks up to 1⁄2 in. long, silky. There are from three to seven flowers in each cluster, the tube 1⁄3 to 1⁄2 in. long, slender, silky-hairy outside, the expanded portion 1⁄2 in. across. Ovary usually silky-hairy, more rarely partly glabrous. Bot. Mag., n.s., t. 360.
Introduced from China by Fortune in 1843, and later from Japan, where it has long been cultivated but is not native. Unfortunately it is short-lived in cultivation. The flower is very like that of a common lilac in form and colour, and when the shoots are well furnished with them the plant is a beautiful object. Shoots 11⁄2 ft long are sometimes made in a season, the upper two-thirds of which will be covered with blossom. These long, slender wands of blossom, the comparatively long-stalked clusters, and especially the opposite leaves, make this daphne very distinct. It is said to require a soil devoid of chalky substances, but its treatment is little understood.
In the New York Botanic Garden there is a remarkable example of this species 10 ft in diameter, which has grown in the open there for more than thirty years and receives no winter protection. Plants from this source are now in cultivation in Britain but have not so far proved better adapted to our climate than the form previously grown. It is probable that D. genkwa is one of those species that fail in this country not through any inherent tenderness but from lack of summer heat and sun. The average July temperature in New York is 74°F, at Kew 63°F – a very significant difference. Mr B. N. Starling, in an interesting letter, suggests that abundant moisture during the growing season is also desirable, remarking that in China this daphne is often found growing at the margins of ricefields. It is also more than probable that it resents stagnant moisture at the root during the winter. A deep, rubbly, well-drained soil in a warm corner, artificially watered during the growing season, are perhaps the conditions that would best suit this beautiful species.