Loosely branched shrub, 1–2 m; young shoots and petioles covered with adpressed grey-brown hairs. Leaves of two kinds; spring leaves deciduous, 3–9 × 2–3.5 cm, elliptic to lanceolate, apex acute, both surfaces with scattered adpressed pilose hairs, lower surface paler than upper; summer leaves persistent, 3–4 × 1–1.5 cm. Pedicels densely covered with fulvous eglandular or gland-tipped bristles. Flowers 2–6 per inflorescence; calyx c.5 mm; corolla rose-red to scarlet, with dark flecks on upper lobes, broadly funnel-shaped, 45–60 mm; stamens 10; ovary covered with eglandular or gland-tipped hairs. Flowering April-May. Royal Horticultural Society (1997)
Distribution Japan Ryukyu Islands
Habitat s.l.-400 m
RHS Hardiness Rating H3
Conservation status Least concern (LC)
An evergreen azalea, stiffly branched, bushy, probably up to 6 ft high, the branchlets having the dark forward-pointing bristles of this group. Leaves 1 to 3 in. long, 1⁄2 to 11⁄2 in. wide; oblanceolate, or oval, tapered at the base, terminated by a short mucro; glabrous and dark green above, paler and with dark appressed hairs like those of the stem beneath and on the margins; stalk 1⁄4 to 1⁄2 in. long. Flowers up to six in a cluster, on hairy pedicels. Calyx with rounded or obtuse lobes, glandular-ciliate and appressed-hairy, up to 1⁄4 in. long, occasionally longer and acute. Corolla rose-red to scarlet, with darker markings on the upper lobes, broadly funnel-shaped, up to almost 4 in. across, the lobes five, rounded at the apex. Stamens ten, nearly as long as the corolla, downy towards the base. Ovary clad with appressed bristly hairs and glands; style glabrous. Bot. Mag., t. 8478. (s. and ss. Obtusum)
Native of the Ryukyu Archipelago, commonest, according to Wilson, in the Okinawa group of islands and on Takuno island. It is not a native of Japan proper, but is cultivated in the southern parts of the country. It was introduced by Messrs Notcutt about 1909 and received an Award of Merit when they exhibited it at the Temple Show in 1911. The seedlings raised by them varied much in colour. Its best forms are some of the richest coloured of all azaleas, but it is not very hardy, and needs a warmer climate than that of Kew.
Pedicels, calyx and ovary glandular.
R. yakuinsulare Masamune
Pedicels, calyx and ovary eglandular.
Taxonomic note (incl. R. yakuinsulare Masamune)