An evergreen shrub or small tree from 10 to 25 ft high; young shoots pale grey with down. Leaves oblanceolate, 5 to 101⁄2 in. long, 11⁄2 to 31⁄2 in. wide, dark green and glabrous above, grey white and downy beneath; stalk 1 in. or less long, cylindrical, pale yellowish green like the midrib. Flowers borne rather loosely in a truss fifteen to twenty together. Calyx a mere rim; flower-stalks downy, 3⁄4 to 1 in. long. Corolla between funnel- and bell-shaped, up to 21⁄2 in. wide, five- to seven-lobed, white or rose-tinted, with a crimson blotch at the base and sometimes similarly coloured spots on the upper lobes. Stamens double the number of corolla-lobes, scurfy at the base; ovary downy; style glabrous. Bot. Mag., n.s., t. 462. (s. Falconeri)
Native of N.W. Yunnan, where it was found on the Mekong-Salween divide by the Abbé Soulié in 1898, flowering in March; afterwards in the same region by Père Monbeig and by Forrest who introduced it. It occurs up to 13,000 ft altitude, and is hardy in climates like that of the inland parts of Sussex and Hampshire. It is a handsome-leaved species of the Falconeri series, distinct therein by reason of the grey-white colouring of various parts. It has suffered from Lionel de Rothschild's condemnation of it as 'a long way the worst rhododendron in the series', with small white flowers and not worth growing. In fact, some plants raised from Forrest 25622 and 25872 have large, very beautiful flowers.
R. coriaceum received an Award of Merit when shown by the Crown Estate Commissioners, Windsor Great Park, on April 14, 1953 (clone 'Morocco').