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 basilicum' from the website Trees and Shrubs Online (treesandshrubsonline.
Shrub or small tree, 3–10 m; bark rough. Leaves 17–25 × 8.5–13 cm, obovate to oblanceolate, upper surface with deeply impressed veins, lower surface covered with a dense two-layered indumentum, the upper layer greyish at first, usually becoming rufous, composed of only slightly fimbriate cup-shaped hairs, the lower layer compacted; petioles strongly flattened and winged. Flowers 15–25, in a dense truss, 8-lobed, fleshy, cream or pale yellow, with a crimson blotch, obliquely campanulate, nectar pouches lacking, 35–50 mm; stamens 16; ovary densely rufous-tomentose. Flowering April-May. Royal Horticultural Society (1997).
Distribution Myanmar NE China W Yunnan
Habitat 3,000–3,700 m
RHS Hardiness Rating H4
Awards AM 1956 (Col Lord Digby, Minterne, Dorset) from Forrest 24139; flowers pale whitish cream, with a crimson blotch.
Conservation status Near threatened (NT)
Taxonomic note The flattened petioles and yellow flowers distinguish this from the remaining species in the subsection. Royal Horticultural Society (1997).
An evergreen shrub or small tree up to 30 ft high; young shoots clothed with red-brown, soft felt. Leaves oval or obovate, rounded at the apex, less so or broadly tapered at the base, 6 to 13 in. long, about half as much wide, dark green and ultimately glabrous above, covered beneath with a rich red-brown down; stalk very stout, flattened above, up to 11⁄4 in. long. Flowers opening in April, numerously and closely packed in a truss 5 in. or more wide. Calyx a mere wavy rim; flower-stalks 1 to 11⁄3 in. long, downy. Corolla broadly and obliquely bell-shaped, eight-lobed, 11⁄2 in. wide, pale yellow flushed with rose and blotched with crimson at the base. Stamens sixteen, nearly or quite glabrous. Ovary densely clothed with down; style glabrous. (s. Falconeri)
Native of N.W. Yunnan and bordering parts of upper Burma, but of limited distribution; discovered by Forrest in 1910 on the Shweli-Salween divide and introduced by him in 1912. His F.24139 is also from this area and a plant raised from it received an Award of Merit when shown by Col. The Lord Digby, Minterne Abbey, Dorset, in 1956. It is also in cultivation from Farrer 873 (Hpimaw pass, Nmai-Salween divide) and Rock 03904. It occurs at altitudes of up to 11,000 ft.
R. basilicum is perfectly hardy south of London in light woodland.