Rhododendron leptothrium Balf. f. & Forr.

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Credits

Article from Bean's Trees and Shrubs Hardy in the British Isles

Recommended citation
'Rhododendron leptothrium' from the website Trees and Shrubs Online (treesandshrubsonline.org/articles/rhododendron/rhododendron-leptothrium/). Accessed 2024-03-18.

Genus

Synonyms

  • Rhododendron australe Balf. f. & Forr.
  • Rhododendron bachii H.Lev.

Other taxa in genus

Glossary

calyx
(pl. calyces) Outer whorl of the perianth. Composed of several sepals.
corolla
The inner whorl of the perianth. Composed of free or united petals often showy.
ovary
Lowest part of the carpel containing the ovules; later developing into the fruit.
apex
(pl. apices) Tip. apical At the apex.
calyx
(pl. calyces) Outer whorl of the perianth. Composed of several sepals.
ciliate
Fringed with long hairs.
glabrous
Lacking hairs smooth. glabrescent Becoming hairless.
lanceolate
Lance-shaped; broadest in middle tapering to point.
midrib
midveinCentral and principal vein in a leaf.
mucro
Short straight point. mucronate Bearing a mucro.
orbicular
Circular.
ovate
Egg-shaped; broadest towards the stem.
style
Generally an elongated structure arising from the ovary bearing the stigma at its tip.

Credits

Article from Bean's Trees and Shrubs Hardy in the British Isles

Recommended citation
'Rhododendron leptothrium' from the website Trees and Shrubs Online (treesandshrubsonline.org/articles/rhododendron/rhododendron-leptothrium/). Accessed 2024-03-18.

Shrub, to 8 m. Bark red-brown, peeling. Leaves 3.5–12 × 1.5–3.5 cm, narrowly elliptic to lanceolate, apex acute to blunt. Flowers single, borne laterally below vegetative buds, rose to purple, with darker markings, rotate, c.50 mm across, tube short, lobes spreading; stamens 5. Flowering April-May. Royal Horticultural Society (1997)

Distribution  Myanmar NE China SW

Habitat 2,150–3,300 m

RHS Hardiness Rating H4

Conservation status Least concern (LC)

An evergreen, diffusely branched shrub up to 20 ft high in the wild, with slender downy twigs becoming grey, the down persisting at least two years. Leaves thin, oval-lanceolate, rounded at the base, tapering at the apex to a short mucro, 112 to 3 in. long, 58 to 1 in. wide, at first a pleasing purplish red then dark green and glabrous except for the midrib, which is downy above and below; stalk 14 to 58 in. long, covered with grey down. Flowers solitary from the clustered terminal leaf-axils, opening in May; pedicels slender, 58 in. long, downy, rosy purple. Calyx with five ovate or oblong lobes 38 in. long, ciliate. Corolla deep magenta rose with crimson spots, about 134 in. wide, five-lobed, the lobes oblong and as long or longer than the tube, which is downy inside. Stamens five, the lower half downy. Ovary covered with sticky glands; style glabrous. Bot. Mag., n.s., t. 502. (s. Ovatum)

Native of W. Yunnan, China; introduced by Forrest in 1914 from the border between Yunnan and Burma (western flank of the Shweli-Salween divide), but described from specimens collected by him in 1918 on the Mekong-Yangtse divide. A closely related species occurs in Burma. R. leptothrium is closely allied to R. ovatum, differing in having the leaves mainly elliptic, in its deeper coloured corollas with oblong (not orbicular) lobes, and in having the calyx-lobes edged with short, gland-tipped bristles. It is a tender species – much less hardy than the cultivated form of R. ovatum. It is botanically interesting, but not of much ornamental value, though the young growths are attractively tinted.