An evergreen shrub of thin, lanky habit, 6 to 8 ft high, young shoots slender but rather rigid, clothed with pale wool and long hairs. Leaves distributed along the branchlets, narrowly oval to oblong-lanceolate, pointed, tapered at the base, 11⁄2 to 31⁄2 in. long, 3⁄4 to 1 in. wide, dark green and with stiff short hairs above; paler, scaly, and hairy beneath especially on the prominent midrib and veins; stalk 1⁄8 to 1⁄4 in. long. Flowers produced in March or April from several of the axils of the terminal leaves in two- to four-flowered umbels, the whole forming a many-flowered cluster 3 or 4 in. wide. Calyx hairy and scaly, 1⁄8 in. long, with five deep, pointed lobes. Corolla white or pale pink, 11⁄4 in. wide, with a short tube and five ovate, blunt, spreading lobes 1⁄2 in. long. Stamens ten, with pink stalks 1⁄2 in. long, downy at the base. Ovary scaly and clothed with short, whitish hairs; style 3⁄4 in. long, hairy towards the base. Bot. Mag., 7159. (s. Scabrifolium)
Native of Yunnan, China; discovered by Delavay in 1883, introduced to the Jardin des Plantes at Paris in 1885, whence plants were sent to Kew in 1888 that flowered two years later. It is an interesting and (in its clothing of stiff hairs and flatly open flowers) a distinct species, but not one of the more attractive ones. It was rediscovered and introduced in 1913 by Forrest, who found it in other parts of Yunnan in open situations up to 11,000 ft. It is, however rather tender. Its nearest ally is R. spicijerum, which has a similar indumentum on its stems and leaves, but much smaller leaves.
From the Supplement (Vol. V)
var. spiciferum (Franch.) Cullen R. spiciferum Franch. – According to Dr Cullen, this has all the essential characters of R. scabrifolium, differing in its more narrowly funnel-shaped corollas and narrower leaves. A native of central and southern Yunnan, possibly extending into Kweichow. In 1964 Mr Davidian included in R. spiciferum the very similar R. pubescens (q.v. in this supplement) and it may be that some plants of the latter are now under the label R. spiciferum. The origin of the plants grown as R. spiciferum before that date is uncertain (there is no record of its having been collected by Forrest). Most probably they were raised from seeds gathered by Chinese collectors, who were employed after Forrest's death by the Hon. H. D. McClaren (the second Lord Aberconway).
R. scabrifolium var. spiciferum is less hardy than the more northern R. pubescens.