Rhododendron stewartianum Diels

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Peter Norris, enabling the use of The Rhododendron Handbook 1998


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

Recommended citation
'Rhododendron stewartianum' from the website Trees and Shrubs Online (treesandshrubsonline.org/articles/rhododendron/rhododendron-stewartianum/). Accessed 2024-05-24.



  • Rhododendron aiolosalpinx Balf. f. & Farrer
  • Rhododendron nipholobum Balf. f. & Farrer

Other taxa in genus


The inner whorl of the perianth. Composed of free or united petals often showy.
Lowest part of the carpel containing the ovules; later developing into the fruit.
Traditional English name for the formerly independent state known to its people as Bod now the Tibet (Xizang) Autonomous Region of the People’s Republic of China. The name Xizang is used in lists of Chinese provinces.
Bluish or greyish waxy substance on leaves or fruits.
The inner whorl of the perianth. Composed of free or united petals often showy.
Lacking hairs smooth. glabrescent Becoming hairless.
Bearing glands.
Plant originating from the cross-fertilisation of genetically distinct individuals (e.g. two species or two subspecies).
A covering of hairs or scales.
Generally an elongated structure arising from the ovary bearing the stigma at its tip.


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

Recommended citation
'Rhododendron stewartianum' from the website Trees and Shrubs Online (treesandshrubsonline.org/articles/rhododendron/rhododendron-stewartianum/). Accessed 2024-05-24.

Shrub, 0.5–2.5 m; bark smooth or rough, peeling on smaller branches; young shoots often glandular. Leaves 4–12 × 2–6.5 cm, obovate to elliptic, base rounded, upper surface glabrous, lower surface with a mammillate epidermis and a thin more or less persistent to evanescent indumentum interspersed with sessile glands; petioles usually glabrous occasionally with a few glands. Flowers 3–7, in lax truss; calyx (2–)5–15 mm, cupular; corolla white or cream to pale (rarely deep) rose, with or without purple flecks, campanulate to tubular-campanulate, with nectar pouches, 35–55 mm; ovary usually densely glandular, style glabrous. Flowering February-April. Royal Horticultural Society (1997).

Distribution  Myanmar NE China SE Tibet, NW Yunnan

Habitat 3,000–4,250 m

RHS Hardiness Rating H4

Awards AM 1934 (L. de Rothschild, Exbury).

Conservation status Least concern (LC)

Taxonomic note This is a variable species, especially with respect to the flower colour. It is allied to R. eurysiphon and perhaps also R.eclecteum, though the presence of a more or less persistent leaf indumentum will distinguish it from these two species. Royal Horticultural Society (1997).

An evergreen shrub up to 10 ft high, young shoots glabrous. Leaves obovate to oval, 2 to 412 in. long, more or less rounded at both ends, grey-green above, undersurface covered with a powdery indumentum or with a thin veil of hairs; stalk about 14 in. long. Flowers in trusses of three to seven, opening in February, March, or April. Corolla tubular-campanulate, 134 in. long and wide, with five rounded, notched lobes; the colour, according to Farrer, ranging from ‘cream and pure white through all flushes and shades of pink to rich deep rose’; another collector found plants with ‘scarlet red’ flowers, and others are described as ‘deep crimson’. Stamens ten, downy at the base. Ovary glandular; style glabrous. (s. and ss. Thomsonii)

Native of N.E. Burma and of bordering parts of S.E. Tibet and N.W. Yunnan, with its greatest concentration in the mountains between the Salween and the upper eastern Irrawaddy, from 26° 20′ N. to about 28° 50′ N.; discovered by Forrest in 1904; introduced by Farrer and Cox in 1919 from the Chimi-li and simultaneously by Kingdon Ward from Imaw Bum, a few miles farther west. Forrest sent numerous batches of seed during the 1920s, some from the Chimi-li but mostly from farther north. Kingdon Ward’s 8294 from the Mishmi Hills, Assam, is near to R. stewartianum.

R. stewartianum first flowered in the spring of 1930 at Exbury, Logan, and Bodnant, and received an Award of Merit when shown from the first-named garden on March 20, 1934. It is remarkably variable in the colour of its flowers and Farrer found, in one area, plants growing together bearing flowers of nearly all the shades mentioned above. In some plants the colour is deepest near the margin of the corolla, paling downwards. Although quite hardy, R. stewartianum flowers too early to be of value for most gardens – in some years it is in full bloom in February.

From the Supplement (Vol. V)

Some field-specimens placed under R. stewartianum are natural hybrids (Rev. 2, p. 426).

R. eclecteum – The var. bellatulum is not recognised in the Edinburgh revision.

As mentioned under R. chaetomallum in this supplement, hybrids occur in the wild between that species and R. eclecteum (R. × hemigymnum).

R. eurysiphon Tagg & Forr. – This species was formerly grouped with R. martinianum in s. Thomsonii ss. Selense, but Dr Cullen points out that the corollas have nectaries, a character that excludes it from subsect Selensia. Its proper place is in subsect. Thomsonia, near to R. eclecteum, of which it may be a natural hybrid (Rev. 2, pp. 426–8).

R eclecteum Balf. f. & Forr

Allied to R. stewartianum, but with the leaves always glabrous beneath except for the sometimes hairy midrib. Also, in its typical state, it is very easily distinguished by its almost sessile, obovate leaves, slightly cordate at the base; in the original description their shape was likened to that of a Jargonelle pear. It appears to be a native mainly of the region from the Mekong-Salween divide around Ka-kar-po westward to upper Burma but has also been collected in S.W. Szechwan. The variation in colour is as remarkable as it is in R. stewartianum. Perhaps the finest, and certainly the most distinct, are those with pure white flowers, with blackberry-coloured nectar-pouches and anthers. Such is Kingdon Ward’s 6869, from the Seinghku valley, north-west upper Burma. His 6900, from the same area, has flowers of a deep glowing pink. Unfortunately it is just as early-flowering as R. stewartianum.

var. bellatulum Tagg

Leaves with distinct petiole, more or less oblong, rounded or obtuse at the base.

var. brachyandrum (Balf. f. & Forr.) Tagg

R. brachyandrum Balf. f. & Forr

Flowers deep rose or crimson.