A modern reference to temperate woody plants, including updated content from this site and much new material, can be found at Trees and Shrubs Online.

Rhododendron keiskei Miq.

Modern name

Rhododendron keiskei Miq.

An evergreen shrub 6 ft high in the wild; young branches slightly scaly. Leaves 112 to 212 in. long, 34 to 114 in. wide, oval-oblong, pointed at the apex, rounded or tapered at the base, more or less scaly on both surfaces, but especially beneath; stalk about 14 in. long. Flowers pale, rather dull yellow, 114 to 2 in. across, in clusters of about four or five; corolla broadly bell-shaped; calyx undulated into five very shallow lobes; stamens ten, slightly downy; flower-stalk scaly, 12 to 34 in. long. Blossoms in April and May. Bot. Mag., t. 8300. (s. and ss. Triflorum)

Native of Japan from the main island southward as far as Yakushima; introduced in 1908 and quite hardy. It is a rather variable species, both in habit and in the size and shape of its leaves. In his collection at The Grange, Benenden, Kent, Capt. Collingwood Ingram has a tall-growing plant which he considers to be a good match for typical R. keiskei, in which the leaves are lanceolate, acute, up to 3 in. long and 34 in. wide, and the petioles bristly when young. The commonly cultivated form, by contrast, is of low-growing habit and has shorter and relatively broader leaves, which are obtuse or subacute at the apex, with a stout midrib and glabrous petioles. Ingram considers the latter to represent a distinct species, which he has named R. laticostum (R.C.Y.B. 1971, pp. 28-30). These two cultivated forms are certainly very distinct, but the difference would probably be much less clear-cut if a wide range of wild specimens were examined. In the same article, Ingram published a second species, R. trichocalyx, described from a cultivated plant. He informs us that he is now satisfied that the plant in question is a hybrid of garden origin.

cv. ‘Yaku Fairy’. – A prostrate plant with flowers about 134 in. across in trusses of two to five. Leaves lanceolate, up to 112 in. long. Award of Merit April 14, 1970, when shown by Barry N. Starling. It was collected on Mt Kuromi, Yakushima (see R.C.Y.B. 1971, pp. 104-6).



Other species in the genus