Kindly sponsored by
Peter Norris, enabling the use of The Rhododendron Handbook 1998
New article for Trees and Shrubs Online.
'Rhododendron quadrasianum' from the website Trees and Shrubs Online (treesandshrubsonline.
Shrub or small tree to 6 m, terrestrial, sometimes epiphytic; young stems finely scaly and minutely white-hairy. Leaves 1.5-3.5 x 0.5-1.3 cm, narrowly elliptic, elliptic, obovate or spathulate, the apex obtuse, rounded, often retuse, the margin strongly reflexed sometimes almost revolute, the base narrowly to broadly tapering; upper surface finely silvery or brown-scaly, the midrib impressed, the laterals 1-3 pairs mostly obscure; lower surface with the midrib strongly, weakly or hardly raised, the laterals smooth, the scales well spaced, circular or slightly lobed with small to large centres. Flowers 1-4 per umbel, half hanging to vertically hanging; calyx a low scaly and/or hairy disc; corolla red, cylindrical, 1.3-2.5 x 0.8-1.4 cm, usually scaly and laxly hairy outside, sometimes scaly only; stamens 10, mostly irregularly arranged in the mouth of the flower sometimes roughly grouped on the lower side; ovary scaly only, the style glabrous. Royal Horticultural Society (1997)
Distribution Indonesia possibly also in Celebes Philippines widespread
Habitat 1,000-2,500 m
RHS Hardiness Rating H2
Conservation status Least concern (LC)
Bornean specimens are now all attributable to other species (see Rhododendrons of Sabah 1988, G. Argent, A. Lamb, A. Phillipps & S. Collenette, Sabah Parks Publication No. 8). A variable species with different forms coming from the different mountain groups in the Philippines, the most commonly cultivated form is var. rosmarinifolium (Vidal) Copel.f. with elongate-obovate leaves, with pedicels pubescent and scaly and corolla up to 1.5cm long. Royal Horticultural Society (1997)