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 micranthum' from the website Trees and Shrubs Online (treesandshrubsonline.
Shrub, to 2.5 m; young shoots scaly and puberulent. Leaves (1.6-)3-4(-5.6) x (0.5-)1-2.5 cm, oblong-elliptic, sometimes narrowly so, apex acute, midrib sparsely puberulent above, lower surface with brown broad-rimmed touching or overlapping scales. Flowers usually more than 20, in a dense terminal inflorescence with a conspicuous rhachis; pedicels puberulent; calyx lobes 1-2 mm, triangular, ciliate; corolla white, unspotted, funnel-campanulate, 5-8 mm, outer surface densely scaly; stamens 10, longer than corolla; ovary scaly, impressed, below the straight style that is shorter than the stamens, and glabrous or with a few hairs at base. Flowering May-July. Royal Horticultural Society (1997)
Distribution China Heilongjiang, Jilin, Hebei, Hubei, Gansu, Shanxi, Shandong, Sichuan South Korea
Habitat 1,600-2,600 m
RHS Hardiness Rating H6
Conservation status Least concern (LC)
Taxonomic note A distinct species, though in some respects resembling members of Subsect. Ledum. Royal Horticultural Society (1997)
An evergreen shrub of bushy form, ultimately 4 to 6 ft high; branches slender, scaly, and slightly downy when young. Leaves narrowly oval or oblanceolate, tapering at both ends, 3⁄4 to 11⁄2 in. long, 1⁄4 to 1⁄2 in. wide, glabrous above, very scaly beneath; stalk 1⁄8 in. or less long. Flowers dull white, 1⁄3 to 1⁄2 in. across, numerous and densely packed in a short, terminal, rounded raceme 11⁄4 to 11⁄2 in. across, on slender, scaly stalks up to 3⁄4 in. long. Calyx with linear lobes 1⁄16 in. long. Corolla bell-shaped at the base, with five flatly spreading, oval lobes as long as the tube; stamens ten, longer than the corolla, not downy. Style shorter than the stamens, glabrous. Bot. Mag., t. 8198. (s. Micranthum)
Native of North and Central China, and of Korea; first collected by the French missionary d’lncarville in the middle of the 18th century in the mountains north of Peking and described in 1837 from a later collecting in the same area; apparently not introduced to Britain until Wilson sent seeds to Messrs Veitch from W. Hupeh in 1901. According to him it is a rare plant in Hupeh, growing in cliffs at 5,000 to 6,000 ft and favouring ‘fully exposed and windswept rocky places’. It is remarkably distinct in its racemes of small, numerous flowers, which open in May, and give the plant at that time a strong resemblance to Ledum groenlandicum. Still, it is not in the front rank of rhododendrons.