Shrub or tree, 1.8 m; young shoots more or less densely rufous- to white-stellate-tomentose though often soon becoming glabrous. Leaves 7–15 × 2.8–6 cm, elliptic to oblanceolate, lower surface glabrous when mature, or with a rufous stellate indumentum persisting towards the base; petioles more or less glabrous when mature. Flowers 5–15 in a truss, white to pink, with or without a purple blotch, campanulate, nectar pouches lacking, 35–50 mm; ovary densely to very sparsely brownish stellate-tomentose, style glabrous. Flowering May-June. Royal Horticultural Society (1997)
Distribution China W Sichuan, NE Yunnan
Habitat 3,500–4,500 m
RHS Hardiness Rating H4
Conservation status Near threatened (NT)
For this species, rare in cultivation, see Rev. 2, p. 271; Rhododendron Year Book 16, p. 161 (original description of R. cookeianum); and Peter Cox, The Larger Species of Rhododendron, pp. 304–5 (as R. cookeianum). Originally placed in series Irroratum ss. Parishii, it is considered by Dr Chamberlain to belong to subsect. Maculifera.
Lower surface of leaves with a persistent rufous stellate tomentum towards the base.
Var. exquisitum has recently come into cultivation so it should soon be possible to confirm the apparently small differences between the two varieties.
Lower surface of leaves more or less glabrous when mature.
Distribution China (W Sichuan, ?Yunnan).
Taxonomic note (incl. R. cookeanum Davidian)