Shrub, 0.6–5 m; young shoots scaly Leaves 2.7–6.2 × 1.1–2 cm, lanceolate to oblong, apex acute, upper surface scaly, midrib sometimes hairy; lower surface densely covered in small brown, narrow-rimmed scales that are 1–2 × their own diameter apart. Flowers 3–6(–10), in a terminal inflorescence; calyx disc-like, sometimes ciliate; corolla usually pink to lavender, sometimes with darker spots, widely funnel-campanulate, zygomorphic, (19–)23–33 mm, stamens 10; ovary densely scaly, impressed below the decimate style that is glabrous or puberulent at base. Flowering April-May. Royal Horticultural Society (1997)
Distribution China N Yunnan, W Sichuan, Guizhou
Habitat 2,000–3,300 m
RHS Hardiness Rating H5
Awards AM 1935 (Lord Aberconway, Bodnant) and FCC 1953 (Lord Aberconway and National Trust, Bodnant) to a pale rose form. AM 1993 (David Clulow, Tilgates, Bletchingly, Surrey) to a clone 'Ruth Lyons'; trusses 8-10-flowered, corolla deep purplish pink with light red spotting in upper throat. AGM 1993
Conservation status Least concern (LC)
Taxonomic note This species may be recognized from R. yunnanense and its immediate allies by a combination of the relatively dense narrowly rimmed leaf scales and the size of the flowers. Royal Horticultural Society (1997)
An evergreen shrub up to 10 ft high; young shoots at first purplish red, scaly. Leaves narrowly oblong-lanceolate, 1 to 21⁄2 in. long, 1⁄3 to 7⁄8 in. wide, dark glossy green and slightly scaly above, dull brown and densely scaly beneath. Flowers opening in April in clusters of two to five at the end of the shoot and in the terminal leaf-axils, each on a scaly stalk 1⁄3 to 1⁄2 in. long. Corolla about 11⁄4 in. long, 13⁄4 in. wide, pale rose with a few red dots on the upper side. Stamens ten, paler than the corolla, downy at the base. Ovary covered with minute scales; style glabrous. Bot. Mag., tt. 8605, 8665, 8759. (s. Triflorum ss. Yunnanense)
Native of W. Szechwan and N.W. Yunnan; discovered and introduced by Wilson in 1904, but described from a specimen he collected four years later during his first expedition for the Arnold Arboretum, during which he again sent seeds. It grows up to 10,000 ft altitude and according to Wilson is very common near Kangting (Tatsien-lu), in sunny exposed places, where it flowers with great freedom. Seen at its best R. davidsonianum is a very pretty shrub, its flowers delicate in hue and abundant, varying in shade and spotting. A fine pink-flowered form grown at Bodnant received a First Class Certificate on May 3, 1955, when shown by Lord Aberconway and the National Trust. It had received an Award of Merit twenty years earlier.
† R. tatsienense Franch. – Like that of Wilson’s R. davidsonianum, the type of this species was collected in the area of Kangding (Tatsien-lu), by the French missionary Père Soulié. It differs from that species in its relatively broader leaves and smaller flowers and is also near to R. siderophyllum, but lacks the tightly packed compound inflorescence of that species. It is cultivated, though rarely, from seed-collections by Forrest in south-west Szechwan and north-west Yunnan. Lancaster 951, collected south-west of Kangding in 1981, probably belongs to R. tatsienense.