Rhododendron stenopetalum (Hogg) Mabb.

Low shrub, 0.3–1 m; young shoots covered with greyish spreading-pilose, sometimes gland-tipped, hairs, also with a few bristles. Leaves of two kinds; spring leaves deciduous, 2.5–7 × 1.5–2.5 cm, ovate-elliptic, apex acute, lower surface with gland-tipped hairs, with a few bristles on the midrib and main veins; summer leaves persistent, 1.2–2 × 0.3–0.6 cm; petioles densely pilose, also with a few flattened setae. Pedicels covered with long spreading pilose, partly gland-tipped hairs. Flowers 2–10 per inflorescence; calyx 15–30 mm, lobes lanceolate to broadly oblong; corolla lilac-pink to rose-purple, with purple flecks on upper lobe, broadly funnel-shaped, 35–50 mm; stamens 5(–7); ovary covered with gland-tipped bristles, style glabrous. Flowering May-June. Royal Horticultural Society (1997)

Distribution  Japan Honshu, Shikoku

Habitat 150–400 m

RHS Hardiness Rating H4

Awards AM 1984 (E. de Rothschild, Exbury) as R. macrosepalum 'Linearifolium'; trusses 3-5-flowered, corolla divided almost to base, with segments widely deflexed, red-purple with some darker marking.

Conservation status Least concern (LC)

Taxonomic note (incl. R. macrosepalum Maxim.) Royal Horticultural Society (1997)