Straggling shrub, (0.5–)1–5(–7) m; young shoots scaly, mature bark smooth and peeling, reddish brown. Leaves usually evergreen, 3.8–6.5 × 2–3.2 cm, ovate to lanceolate or elliptic, apex acute, upper surface lacking scales, glabrous, lower surface greyish brown, densely covered with small almost rimless brown scales. Flowers 2–4, in a loose terminal inflorescence; calyx small, scaly, not ciliate; corolla pale yellow, sometimes suffused with red, sometimes with greenish to red flecks, zygomorphic, funnel-shaped to widely funnel-shaped, 21–30 mm, outer surface densely scaly, pubescent at sinuses; stamens 10; ovary scaly, impressed below the declinate, glabrous or (rarely) puberulent at base, style. Flowering May-June. Royal Horticultural Society (1997)
Distribution Bhutan Myanmar N China S Tibet India Bengal, Manipur
Habitat 2,300–3,650 m
RHS Hardiness Rating H5
Conservation status Least concern (LC)
An evergreen shrub 6 to 10 ft high with glabrous, red, peeling bark; young shoots slender, glaucous, scaly. Leaves ovate-lanceolate, rounded at the base, sharply pointed, 2 to 3 in. long, 1 to 11⁄4 in. broad, bright green and glabrous above, glaucous and thickly furnished with scales beneath; stalk 1⁄4 to 1⁄3 in. long. Flowers fragrant, opening in May and June, usually in threes, at the end of the shoot when young growths are pushing. Calyx small, shallowly undulated; flower-stalks 1⁄2 to 7⁄8 in. long. Corolla pale yellow spotted with green, with a short funnel-shaped tube and five spreading oblong lobes giving the flower a diameter of 11⁄2 to 2 in., scaly outside. Stamens ten, 1⁄2 to 1 in. long, downy towards the base; ovary scaly; style longer than stamens, glabrous. (s. and ss. Triflorum)
Native of the eastern Himalaya; discovered by J. D. Hooker in the Sikkim Himalaya in 1849 and introduced by him. It is not a showy plant, although the flowers are interesting in their unusual colour. The red, semi-transparent, loose bark is also attractive with sunlight behind it. It is hardy.
The var. mahogani is not recognised in the Edinburgh revision, understandably so, as it is only a minor colour-form linked to the typical state by intermediates.
var. bauhiniiflorum (Hutch.) Cullen R. bauhiniiflorum Hutch. – The only distinguishing character of this variety is the widely expanded flower.
R. bauhiniiflorum Watt ex Hutch.
Corolla very openly funnel-shaped to almost flat. Royal Horticultural Society (1997)
RHS Hardiness Rating: H5
The two varieties recognized here are distinguished only by the shape of the corolla. They apparently have different geographical distributions. Royal Horticultural Society (1997)
Corolla funnel-shaped to widely funnel-shaped.
Distribution Nepal, India (Sikkim, W Bengal, Arunachal Pradesh), Bhutan, N Burma, China (S Tibet).
Taxonomic note (incl. R. triflorum Hook.f. var. maltogani Hutch.)