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Rhododendron keysii Nutt.

Modern name

Rhododendron keysii Nutt.

An evergreen shrub 6 ft or more high; the young shoots, the undersurface of the leaves, leaf-stalk, and flower-stalk densely covered with brownish-red, glistening scales. Leaves 2 to 4 in. long, 58 to 114 in. wide, oval-ovate, tapering at both ends; stalk 13 to 23 in. long. Flowers crowded in short clusters, several of which are borne during May and June from buds near the end of the previous year’s shoot, and at the time of flowering surmounted by the young shoot of the current year. Each flower is 34 to 1 in. long, 14 in. wide – a brick-red, cylindrical tube with five small, blunt, yellow teeth at the mouth; calyx very small; flower-stalk 14 in. long. Bot. Mag., t. 4875. (s. Cinnabarinum)

Native of the eastern Himalaya, from Bhutan to the region of the Tsangpo bend; introduced by Booth from Bhutan in 1851. But most of the plants now in collections derive from seed collected by Kingdon Ward in the early winter of 1924 in Pemako, S.E. Tibet, on the southern side of the Doshong La, where it grows in thickets on the southern slopes of the valley or as undergrowth in the forest at 9,000 to 10,000 ft. These plants (KW 6257) are hardier than the form originally introduced from Bhutan but the species, although of some value for its late flowering, is really little more than a botanical curiosity. It is allied to R. cinnabarinum, but the flowers are much smaller, correa-like, and produced from axillary as well as terminal buds.

Award of Merit June 27, 1933 to a form raised from KW 6257 in which the flowers are uniform red except for a slight yellow tinge at the tips, shown by Lionel de Rothschild, Exbury. It was named var. unicolor by Hutchinson.


Genus

Rhododendron

Other species in the genus