Jasminum humile L.
This variable species, native to the Sino-Himalayan region, is represented in gardens from several introductions. The earliest type to reach Europe f. humile, came in the 17th century and was known in British gardens as the ‘Italian Yellow Jasmine’, the plants, according to Philip Miller, ‘being commonly brought from thence by those who come over with the Orange-trees’. This name served to distinguish it from the common yellow jasmine (J. fruticans), on which it was often grafted. It is inferior to the cv. ‘Revolutum’ as a garden plant, having smaller, less fragrant flowers, but is often hardier.
f. farreri (Gilmour) P. S. Green, comb. & stat. nov. J. farreri Gilmour in Bot. Mag., 47 (1934), t. 9351. – A wide-spreading shrub, 6 to 8 ft high. Young stems angled; stems, leaves, and inflorescences lightly pubescent. Leaflets three to five, the terminal 11⁄3 to 31⁄2 in. long, the lateral 1 to 2 in. long. Flowers bright yellow, not fragrant, seven to twelve per inflorescence, borne in June.
Introduced by Farrer from Upper Burma in 1919, under his No. 867, and at first cultivated under the incorrect name of J. giraldii (a synonym of and the pubescent expression of J. floridum).
f. humile. – A nearly evergreen, glabrous shrub. Leaves alternate with three to seven, sometimes nine leaflets, the terminal 3⁄4 to 2 in. long, the lateral 1⁄2 to 11⁄2 in. long. Flowers yellow, often not fragrant, 5 to 10 borne together. Bot. Reg., t. 350. This is the typical form of the species.
This, the ‘Italian Yellow Jasmine’, is native from Afghanistan and W. Pakistan to Burma and China (Yunnan and Szechwan). It has been reintroduced in more recent times both from the Himalayas and, as Forrest 18927, from S.E. Tibet.
cv. ‘Revolutum’ J. revolutum Sims; J. humile var. revolutum (Sims) Stokes – A nearly evergreen, stout, glabrous shrub. Leaves with three to five or seven leaflets, the terminal 11⁄2 to 21⁄2 in. and the lateral 1 to 2 in. long. Flowers yellow, fragrant, six to twelve or more together. Corolla large 3⁄4 to 1 in. diameter; short styled with the acute apices of the two stamens visible in the throat. Bot. Mag., t. 1731, Bot. Reg., t. 178.
The most desirable variant of J. humile, it is somewhat less hardy than the other forms and is sometimes cut back in a bad winter. It grows best in a sheltered position or a temperate greenhouse. In the past it has also been known under the names J. reevesii and J. triumphans.
f. wallichianum (Lindl.) P. S. Green J. wallichianum Lindl.; J. pubigerum D. Don var .glabrum DC.; J. humile var. glabrum (DC.) Kobuski – This shrub differs from f. humile in the more numerous leaflets (seven to thirteen) with the terminal particularly long-acuminate, and relatively few more or less pendulous flowers. Bot. Reg., t. 1409.
Introduced from Nepal, first about 1812, and, more recently, in the 1950s by the expeditions sponsored by the Royal Horticultual Society. The very pubescent plant known as J. pubigerum D. Don is also a form of this species, although not in cultivation.
From the Supplement (Vol. V)
f. wallichianum – This is in cultivation from seeds collected during the University of North Wales Expedition to Nepal in 1971 (B.L. & M. 241) and received an Award of Merit when shown from the Hillier Arboretum.