An evergreen shrub 3 to 4 ft high; young shoots glabrous. Leaves lanceolate to narrowly obovate, usually tapered, sometimes rounded at the base, slenderly pointed, very unequal in size, and varying from 1⁄2 to 4 in. in length, by 1⁄4 to 13⁄4 in. in width; dark green, rather scaly above, pale and freely sprinkled with small scales beneath; stalk up to 1⁄4 in. long. Flowers numerous in one or two terminal clusters. Calyx-lobes 3⁄16 in. long, oblong with a rounded end, scaly. Corolla about 1 in. long, funnel-shaped, deeply lobed, varying from white to clear yellow; stamens ten, protruded, downy at the lower half; seed-vessel about half as long again as the persistent, deeply lobed calyx; style glabrous; ovary scaly. It blossoms in March or April. Bot. Mag., t. 8669. (s. Triflorum ss. Hanceanum).
A native of S.W. Szechwan, discovered by the Rev. E. Faber on Mt Omei about 1886. It was introduced by Wilson from the Mupin area during his first expedition for the Arnold Arboretum (W.882 'bush 1 m. tall, flowers clear yellow'). According to him it is locally very common, forming dense thickets at 8,000 to 10,000 ft. He collected seed again in October 1910, this time from plants 1 to 3 ft high (W.4255).
R. hanceanum is quite an attractive shrub, especially in its dwarfer forms, known in gardens as R. hanceanum nanum (possibly raised from W.4255, see above). One of these, subsequently given the clonal name 'Canton Consul', received an Award of Merit when shown by the Crown Estate Commissioners, Windsor Great Park, on April 16, 1957. The flowers in this plant are described as cream-coloured, but there is another dwarf form in cultivation with flowers of a clear yellow.
R. afghanicum Aitch. & Hemsl. – This species is placed in the Hanceanum subseries by Davidian, but he remarks that it differs from it in many important characters and indeed does not fit well into any of the present series of Rhododendron. It is also geographically far removed from R. hanceanum, found only in a few localities in E. Afghanistan and bordering parts of Pakistan. It is figured in Bot. Mag., t. 8669, but was later lost to cultivation until Hedge and Wendelbo collected seeds in 1969. An interesting account by them on this species in its native habitat will be found in the R.C.Y.B. 1970, pp. 177-81. Although of botanical interest, it is unlikely that R. afghanicum will be of any value as an ornamental.
From the Supplement (Vol. V)
This species is now placed in subsect. Tephropepla. R. afghanicum, mentioned under it, now constitutes the monotypic subsect. Afghanica.