An evergreen shrub or small shrubby tree, with stout, tomentose young stems. Leaves very leathery, dark green, 6 to 8 in., sometimes more, long, 21⁄2 to 3 in. wide, oblong-elliptic, or broadest slightly above or below the middle, obtuse or abruptly acuminate at the apex, rounded to truncate at the base, glabrous above when mature, underside covered with a close, continuous indumentum varying in colour from fawn or grey to cinnamon-brown; petiole up to 1 in. long, tomentose. Inflorescence a terminal truss of up to twenty flowers; rachis variable in length, sometimes 2 in. long; pedicels up to 23⁄4 in. long. Calyx minute. Corolla campanulate, up to 2 in. long, pale yellow, spotted with crimson on the upper lobe and sometimes with a crimson blotch at the base, five-lobed. Stamens ten, downy towards the base. Ovary tomentose; style glabrous. Bot. Mag., t. 8492. (s. Lacteum)
Native of the Himalaya from Nepal to some way east of Bhutan; discovered by J. D. Hooker and introduced by him in 1850. It is a common species in the inner valleys, forming thickets of considerable extent at 12,000 to 14,000 ft. It is not an easy plant to cultivate and early this century was still an exceedingly rare plant in gardens. The best-known example grew in the garden of Miss Clara Mangles at Littleworth near Farnham, and the species received an Award of Merit when she exhibited a truss on May 14, 1913. It is now established in cultivation, but uncommon, though quite hardy. It bears some resemblance to R. lacteum, but in that species the flowers are usually of a much richer colour and unspotted, and the leaves are relatively wider. In cultivated plants the truss of R. wightii tends to be rather lax, though this is not a character of the species as a whole. The flowering time of R. wightii is April or May.
From the Supplement (Vol. V)
The present position of this species is in subsect. Taliensia, as an anomalous member, but it may eventually end up in subsect. Grandia (Rev. 2, p. 365).