Kindly sponsored by
Peter Norris, enabling the use of The Rhododendron Handbook 1998
Article from Bean's Trees and Shrubs Hardy in the British Isles
'Rhododendron hemsleyanum' from the website Trees and Shrubs Online (treesandshrubsonline.
Shrub to tree, 2–8 m; Leaves 10–20 × 4–10 cm, ovate to ovate-elliptic, base cordate, margin undulate, lower surface with scattered punctulate hair bases and a few stalked glands at base, otherwise glabrous. Flowers 5–8, in lax trusses; calyx c.1mm; corolla 6–7-lobed, white, without flecks, campanulate, nectar pouches lacking, 45–60 cm; stamens c.14; ovary and style glandular. Flowering May-June. Royal Horticultural Society (1997)
Distribution China W Sichuan
Habitat 1,100–2,000 m
RHS Hardiness Rating H5
Conservation status Critically endangered (CR)
Taxonomic note A distinctive species with a very restricted distribution in the wild. Royal Horticultural Society (1997)
An evergreen shrub or small tree 10 to 20 ft high; young stems stout, slightly downy; leaf-buds conical. Leaves thick and leathery, oblong or oblong-ovate, 6 to 8 in. long, 23⁄4 to 31⁄2 in. wide, rounded at the apex, deeply cordate-auriculate at the base, upper surface dark green, glabrous, lower surface paler, papillose, lateral veins parallel, in thirteen to fifteen pairs; petioles stout, up to 13⁄4 in. long, sparsely glandular. Flowers borne in May in a racemose corymb of up to twelve; pedicels up to 13⁄8 in. long, glandular and slightly hairy. Calyx very small. Corolla white, funnel-campanulate, seven-lobed, 2 to 25⁄8 in. long. Stamens fourteen, glabrous. Ovary glandular, conoid; style glandular throughout, with a discoid stigma. Pl. Omeienses, t. 30; R.Y.B. 1947, fig. 29. (s. and ss. Fortunei)
This interesting species was discovered by Wilson on Mt Omei in W. Szechwan in 1900 and is said to be endemic to that area. He did not collect seeds, and the species was quite unknown in Britain except from written accounts until Mr E. H. M. Cox obtained seeds from the Rhododendron Test Garden at Portland, Oregon, USA, from which plants were raised and distributed from 1969 onwards by Glendoick Gardens Ltd. He had seen the plants flowering there in May 1964 and published a short note on it in the Rhododendron Year Book for 1966 (p. 133 and fig. 53).
In describing this species Wilson compared it with R. auriculatum, which it resembles in the shape and general appearance of the leaves. But in other respects it seems to be nearer to the Fortunei series, in which it at present resides. Plants from Glendoick are growing well in several gardens, and one flowered in Cornwall in 1973. The wavy edge of the leaves shown by some of these plants seems to be a characteristic of the species.
The original source of the plants now in cultivation was seed sent by H. H. Hu to the Arnold Arboretum in 1937 and further distributed by the University of Washington Arboretum, Seattle.