An evergreen shrub or a small tree up to 30 ft high. Leaves oblong, oblong- lanceolate, or oblong-oblanceolate, 4 to 6 in. long, 7⁄8 to 17⁄8 in. wide, acute to obtuse at the apex, glabrous. Flowers in terminal trusses of ten to fifteen, borne early in spring, sometimes in February; pedicels 3⁄8 to 5⁄8 in. long, floccose and sometimes glandular also. Calyx minute, usually glabrous, but sometimes with the same covering as the pedicels. Corolla five- to seven-lobed, tubular-campanulate, 11⁄2 to 3 in. long, commonly crimson, rose-magenta or blue-magenta, with darker nectar-pouches at the base and sometimes spotted inside, occasionally white or, in the type of R. persicinum, peach-coloured. Stamens ten to fourteen, downy near the base or glabrous. Ovary glabrous or slightly hairy; style glabrous. Bot. Mag., t. 9083. (s. and ss. Irroratum)
Native of N.W. Yunnan and bordering parts of upper Burma; discovered by Forrest below the Sungkwei pass in 1906 and introduced by him. Although hardy in a sheltered position south of London, its flowers are of little beauty and both they and the young growths are often destroyed by frost.