Prostrate or cushion-forming shrub, to 1.5 m. Leaves often bluish, (0.5–)0.7–1.6 × 0.3–0.6(–0.9) cm, broadly elliptic or oblong to ovate, apex rounded to subacute, mucronate, lower surface covered with white or pinkish milky scales that are touching in groups or more scattered. Flowers 1–3(–4) per inflorescence; calyx 3–6 mm, lobes oblong to bluntly triangular; corolla bright lavender-blue to rich purple, funnel-shaped, 10–16(–18) mm; stamens (6–)10, as long as the corolla; ovary scaly, style longer than the stamens, glabrous (rarely scaly and pubescent at base). Flowering April-May. Royal Horticultural Society (1997)
Distribution China N & C Yunnan
Habitat 3,400–4,400 m
RHS Hardiness Rating H6
Awards AM 1914 (G. Reuthe, Keston, Kent); flowers bluish lilac. AGM 1994
Conservation status Least concern (LC)
Taxonomic note R. fastigiatum may be distinguished by the milky scales on the lower surface of the leaves. Royal Horticultural Society (1997)
A moderately compact shrub up to 3 ft high. Leaves oblong-elliptic to oblong- lanceolate, about 3⁄8 in. long in the type, but up to 5⁄8 in. long in some cultivated plants, margins often recurved, upper surface glaucous green, sea-green or deep steely blue, conspicuously dotted with scales, undersides papillose and whitish between the scales, which are opaque, uniform, spaced less than their own diameter apart, sometimes contiguous or even overlapping; petiole very short. Inflorescence terminal, composed of three to five very short-stalked flowers, produced in April or May. Calyx well developed, about as long as the corolla-tube, deeply lobed, scaly outside and fringed with weak hairs. Corolla 3⁄4 to 1 in. wide, in some shade of purple or blue-purple, widely funnel-shaped to almost rotate, with a short tube, hairy inside at the base. Filaments of stamens hairy. Style equalling the stamens or longer, glabrous. (s. Lapponicum)
Native of Yunnan, China; discovered by Père Delavay in the Tali range and described in 1885; introduced by Forrest from the same area in 1906. According to him, it occurs there on cliff-ledges in pine forests on the eastern (drier) side of the range and is the dominant species on the Sungkwei pass some 50 miles north of Tali. It is variable in the colour of its flowers and also in the degree of glaucousness of its foliage, though the leaves are always glaucous when young. In some plants (usually grown as R. impeditum), the leaves remain sea-green or dark blue-green throughout the winter, and are then more decorative than most members of the series. The habit is also variable, some forms being dwarf and slow growing, others more robust and open. The specific epithet refers to the straightness and dense arrangement of the branchlets on the type-specimen, not to the habit of the plant as a whole.
R. fastigiatum received an Award of Merit when shown by Messrs Reuthe in 1914.
R. impeditum – R. litangense, mentioned under this species, is included in it by the Philipsons, with the result that R. impeditum, although typically of low and compact habit, now includes plants growing to about 4 ft high. This merger removes one more difference between R. impeditum and R. fastigiatum, which can be either mound-forming or erect. We are left with no reliable differential character other than that in R. impeditum the leaves at all stages of growth are green, with light brown scales on the undersides (see further on pages 658–9). This is hardly enough to justify species rank for R. impeditum, especially as plants identified as belonging to it occur in the same localities as R. fastigiatum.
In Plantae Wilsonianae (Vol. I, p. 507) it is stated that Wilson found R. fastigiatum in moorlands around Tachien-lu (Kangding) in western Szechwan. In fact this rhododendron belongs to the recently described R. minyaense, for which see in this supplement under R. websterianum.
R. fastigiatum of the 1st edition of this work, not Franch.
R. semanteum Balf. f., nom. inedit