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Rhododendron pentaphyllum Maxim.

Modern name

Rhododendron pentaphyllum Maxim.


R. pentaphyllum var. nikoense Komatsu; R. nikoense (Komatsu) Nakai; R. quinquefolium var. roseum Rehd.

A deciduous, sometimes tree-like azalea up to 20 ft high; young shoots often in tiers, thinly hairy when young, red-brown, becoming grey the second season. Leaves produced in a whorl of five at the end of the shoot, oval to oval-lanceolate, pointed, wedge-shaped at the base, 114 to 212 in. long, half as much wide, midrib downy on both surfaces, margins toothed and ciliate; stalk 18 to 13 in. long, thinly glandular-hairy. Flowers terminal, opening in April or May, solitary or in pairs; flower-stalk 12 in. long, varying from densely glandular to quite glabrous. Calyx with five triangular teeth 15 in. or less long. Corolla bright rose-pink, not spotted, 2 in. wide, with five spreading, rounded, often notched lobes. Stamens ten, of unequal length, downy at the base; anthers yellow; ovary and style glabrous. (s. Azalea ss. Canadense)

Native of central and southern Japan, where it grows in woodland, and is fond of partial shade. Wilson, who saw it wild in the Nikko region, wrote highly of its beauty both in bloom and in autumn, when the leaves change to rich orange and crimson.

In its foliage it resembles R. quinquefolium, but that species has white flowers, and produces its flowers and leafy shoots from the same bud, whereas in R. pentaphyllum they come from separate buds. It is rather slow to flower and prefers a sheltered place in moist leafy soil.

R. pentaphyllum received an Award of Merit on April 14, 1942, when shown by Lord Aberconway, Bodnant.



Other species in the genus