A bushy evergreen shrub up to 8 ft or so high in Hupeh, possibly taller in other parts; young stems downy and slightly glandular bristly. Leaves dark green and glossy, tinged with purple when young, very variable in shape even on the same plant, ovate to broad-elliptic, obovate-elliptic, or rhombic-elliptic, the apex acute or obtuse, sometimes emarginate, always with a very pronounced mucro, base rounded to cuneate, 11⁄4 to 21⁄4 in. long, 3⁄8 to 11⁄2 in. wide, glabrous except for the shortly downy midrib, margins often distinctly serrated with bristle-tipped teeth; petiole 1⁄8 to 3⁄4 in. long. Flowers solitary from axillary buds near the ends of the preceding year's shoots, produced towards the end of May or in June, on glandular-hairy stalks up to 11⁄2 in. long. Calyx-lobes oblong to broadly obovate, rounded at the apex, up to almost 1⁄4 in. long, with or without a fringe of glandular hairs. Corolla pale purple, pink, white, or white suffused with pink, very widely funnel-shaped, almost flat, 1 to 11⁄4 in. wide, with five rounded lobes, the upper three speckled. Stamens five, unequal, the filaments hairy towards the base. Ovary downy; style glabrous. Bot. Mag., tt. 5064, 9375. (s. Ovatum)
Native of Eastern and Central China. It was introduced in 1843-4 by Fortune, who found it growing in the Chusan Archipelago (south-east of Shanghai) and in the tea-district of Chekiang. But the present garden stock almost certainly derives entirely from the seeds sent home by Wilson in 1900 and 1907 from Hupeh, where the species is at its western limit. According to him it is not uncommon in that province at 4,000 to 7,000 ft, on cliffs and in rocky places where it is sheltered from strong winds, and makes there a twiggy bush seldom more than 8 ft high. Both his collections of seed were from the Changyang-hsien district at 5,000 to 7,000 ft. It is a plant from one of these sendings, raised at Caerhays and presented to Kew, that is figured in the Botanical Magazine, t. 9375 (as R. bachii). The earlier plate represents the Fortune introduction.
R. ovatum (the Wilson form) is not entirely hardy and is rather slow-growing and difficult; possibly inadequate summer-heat is the source of the trouble rather than outright tenderness. It is uncommon in gardens, but available in commerce and represented in the Species Collection, Windsor Great Park, by an example about 6 ft high.
R. leptothrium (q.v.) is closely allied to R. ovatum. So too is R. hongkongense Hutch. (Azalea myrtifolia Champion, Bot. Mag., t. 4609), which was included in R. ovatum by Maximowicz, and is discussed and figured under that name by Dr Herklots in R.Y.B. 1949, p. 184 and fig. 56. It is a native of the New Territories of Hong Kong and of Kwangtung; is obviously too tender to be grown out-of-doors in the British Isles and may not be in cultivation. The flowers are pure white, spotted with crimson purple, about 2 in. wide, and the young growths are bright red and pink. Dr Herklots considers it to be the most beautiful of the Hong Kong rhododendrons.