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Rhododendron chamaethomsonii (Tagg & Forrest) Cowan & Davidian

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Sponsor

Kindly sponsored by
Peter Norris, enabling the use of The Rhododendron Handbook 1998

Credits

New article for Trees and Shrubs Online.

Recommended citation
'Rhododendron chamaethomsonii' from the website Trees and Shrubs Online (treesandshrubsonline.org/articles/rhododendron/rhododendron-chamaethomsonii/). Accessed 2026-05-18.

Family

  • Ericaceae

Genus

Other taxa in genus

Glossary

Credits

New article for Trees and Shrubs Online.

Recommended citation
'Rhododendron chamaethomsonii' from the website Trees and Shrubs Online (treesandshrubsonline.org/articles/rhododendron/rhododendron-chamaethomsonii/). Accessed 2026-05-18.

Dwarf shrub, 0.1–1 m. Leaves 2–6 × 1.5–3.2 cm, broadly obovate to broadly elliptic, lower surface glabrous (in cultivation); petioles tomentose and/or stalked-glandular. Flowers (1–)2–5, in a lax truss; calyx 1–7(–15) mm; corolla fleshy, pink to deep crimson, campanulate, with nectar pouches, 25–45 mm; ovary very sparsely to densely rufous-tomentose, sometimes also with at least some glands, abruptly contracted into the glabrous style. Flowering March-May. Royal Horticultural Society (1997)

Distribution  China S Tibet, NW Yunnan

Habitat 4,000–4,600 m

RHS Hardiness Rating H5

Conservation status Vulnerable (VU)


var. chamaethauma (Tagg & Forrest) D.F. Chamb.

Corolla pale to deep pink; calyx minute, 1mm or less; ovary densely hairy.

Distribution China (S Tibet).

Var chamaethomsonii may be no more than a hybrid of R. Forrestii. Var. chamaethauma is however more distinctive and might be a species in its own right.


var. chamaethomsonii

Corolla crimson to carmine; calyx lobes to 7(–15)mm; ovary sparsely hairy, sometimes glandular.

Distribution China (SE Tibet, NW Yunnan).

Awards AM 1932 (Lady Aberconway and Hon H.D. McLaren, Bodnant) as R. repens var. chamaedoxa; flowers crimson.