An evergreen shrub 3 to 6 ft high, with slender but stiff young shoots furnished with glands. Leaves clustered at the end of the shoot, oval inclined to oblong, abruptly tapered towards both ends, ending in a very distinct mucro; 3⁄4 to 13⁄4 in. long, half as much wide; more or less glandular when young, eventually glabrous or nearly so, rather glaucous beneath; stalk 1⁄4 in. long, glandular. Flowers two or three together in a terminal cluster each on a glandular stalk up to 11⁄4 in. long. Calyx small, fringed with glands. Corolla widely funnel-shaped, five-lobed, 1 in. long, 2 in. wide, pale rose with a dark blotch at the base, often speckled with crimson, the lobes reflexed. Stamens ten, downy at the base. Ovary and base of style glandular. (s. Thomsonii ss. Selense)
Native of N.W. Yunnan, bordering parts of S.E. Tibet, and of upper Burma; introduced by Forrest in 1914 and also in cultivation from seeds collected by Rock and by Kingdon Ward. It is named after John Martin, who had charge of the rhododendrons at Caerhays Castle, Cornwall. In its best forms, with clear pink flowers heavily freckled with crimson and borne on a low compact bush, this is one of the most charming of rhododendrons, but is rarely met with in gardens. Kingdon Ward’s 6795 from the Seinghku valley, upper Burma, is unusual in having roundish leaves, recalling those of R. thomsonii.
R. eurysiphon Tagg & Forr. – This species is closely allied to R. martinianum, differing in its campanulate instead of funnel-campanulate corolla. It is possibly a natural hybrid between it and R. stewartianum.