Rhododendron sinogrande Balf. f. & W. W. Sm.

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Credits

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

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

Genus

Infraspecifics

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.
Tibet
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.
appressed
Lying flat against an object.
corolla
The inner whorl of the perianth. Composed of free or united petals often showy.
glabrous
Lacking hairs smooth. glabrescent Becoming hairless.
indumentum
A covering of hairs or scales.
midrib
midveinCentral and principal vein in a leaf.
ovary
Lowest part of the carpel containing the ovules; later developing into the fruit.
stigma
(in a flower) The part of the carpel that receives pollen and on which it germinates. May be at the tip of a short or long style or may be reduced to a stigmatic surface at the apex of the ovary.
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 sinogrande' from the website Trees and Shrubs Online (treesandshrubsonline.org/articles/rhododendron/rhododendron-sinogrande/). Accessed 2024-03-18.

Tree, 6–12 m; bark rough. Leaves 20–70 × 8–30 cm, oblanceolate to broadly elliptic, apex rounded or retuse, minutely apiculate, lower surface with a silvery compacted and agglutinated indumentum, that is largely composed of rosulate hairs; petioles terete. Flowers 8–10-lobed, pale creamy white, with a purple basal blotch, ventricose-campanulate, with nectar-pouches, 40–60 mm; stamens 18–20; ovary densely rufous-tomentose. Flowering April-May. Royal Horticultural Society (1997).

Distribution  Myanmar NE China SE Tibet, Yunnan

Habitat 2,450–4,250 m

RHS Hardiness Rating H4

Awards AM 1922 (Dame Alice Godman, Horsham); flowers creamy white, with a crimson blotch. FCC 1926 (G.H. Johnstone, Trewithian, Cornwall); flowers ivory white, with a big crimson blotch. AGM 1993

Conservation status Least concern (LC)

Taxonomic note The very large leaves with an agglutinated indumentum will distinguish this species. Hybrids between R. sinogrande and R. macabeanum occur in cultivation. Royal Horticultural Society (1997)

An evergreen shrub or a tree up to 35 ft high, the young shoots silvery grey, very stout, and up to 1 in. thick. Leaves oval or oblong, occasionally obovate, rounded at both ends, ordinarily 10 to 20 in. long, 6 to 12 in. wide, at first grey scurfy above, ultimately dark green and glabrous, silvery grey beneath with a closely appressed scurf, not downy or hairy in the ordinary sense of those words; midrib very prominent beneath as are also the fourteen to sixteen pairs of roughly parallel veins springing from it; stalk very stout (up to 12 in. thick) 1 to 2 in. long. Flowers produced in April in a racemose truss of twenty to thirty, and about 9 in. wide; pedicels about 112 in. long, densely woolly. Calyx woolly, fringed with small teeth. Corolla bell-shaped, fleshy, dull creamy white to soft yellow, marked with red patches at the base, 2 in wide, eight- to ten-lobed, the lobes 34 in wide, notched. Stamens eighteen or twenty, downy towards the base, shorter than the corolla. Ovary covered with reddish down; style glabrous; stigma 25 in. wide. Bot. Mag., t. 8973. (s. Grande)

R. sinogrande was discovered by Forrest in 1912, growing at 11,000 ft on the western flank of the Shweli-Salween divide, latitude 250 20′ N. The plants were in fruit and from them the species was introduced to gardens (F.9021). In this area, on the borders between Burma and mid-Yunnan, R. sinogrande is at the south-eastern extremity of its area. From here it ranges along the mountains between the Salween and the eastern branch of the Irrawaddy to some way north of 28° and is also found east of the Salween in this latitude. Most of Forrest’s later sendings are from this northeastern corner, where Burma, China and Tibet adjoin. Westward it ranges across the upper Irrawaddy to the Delei valley in the Mishmi Hills, Assam, but its western limit is uncertain.

R. sinogrande sometimes forms forests single-handed. We passed through whole glades of its gnarled and twisted branches, when its pale yellow globes were alight and shining brighdy under the dark canopy of leaves. Some of the trunks were twenty-four inches round… . One advantage about R. sinogrande is the lateness of its new growth. The great spear-headed buds burst in July, and even in August one can pick out the trees a mile away by the plumes of silver foliage shooting up from ruby-red tubes’ (Kingdon Ward, Plant Hunting on the Edge of the World, p. 277, in reference to R. sinogrande in the Mishmi Hills).

Botanically this is the eastern counterpart of R. grande, differing in the eglandular ovary and pedicels and the shorter and stouter style. In leaf it is much the finer species and in that respect the most splendid and remarkable of all rhododendrons, or indeed of all woody plants hardy in this country. In the Cornish woods, where it first faced the English climate, leaves 212 ft long and 1 ft or more wide have been produced on young plants. It first flowered at Heligan in Cornwall in May 1919. It grows fastest and has attained the largest size in the Atlantic zone, but in woodland gardens south of London it is perfectly at home and flowers just as well as in the milder parts. It is nearly hardy and in some forms completely so. In the Windsor collection some plants were cut to the ground by the freezing winds of February 1956, but others were unharmed or almost so, and none was actually killed (R.C.Y.B. 1957, p. 62).

R. sinogrande was awarded a First Class Certificate when shown by G. H. Johnstone, Trewithen, Cornwall, on March 9, 1926. Four years earlier, Dame Alice Godman had shown a truss from a plant grown under glass at South Lodge, Sussex, and the species had then received an Award of Merit as a tender rhododendron. The plant was a gift from J. C. Williams of Caerhays and also provided the truss figured in the Botanical Magazine.

From the Supplement (Vol. V)

The var. boreale is not recognised in the Edinburgh revision.


var. boreale Tagg & Forr

Described as having rather more leathery and smaller leaves than in the type and flowers soft yellow throughout without markings or pale yellow with a crimson blotch at the base. Introduced by Forrest in 1922 (F.21750). It is sometimes referred to as the ‘northern form’ of R. sinogrande (it was collected in latitude 28° 18′ N.), but Forrest’s 20387, introduced the previous year, came from still farther north and is not mentioned in the description of var. boreale.