A deciduous shrub of vigorous, loose habit, 6 ft or more high; young shoots clothed with a dense white felt. Leaves lanceolate, wedge-shaped at the base, tapering to a long fine point, rather shallowly toothed, each tooth terminated by a short, abrupt, gland-tipped point; they vary much in size according to the vigour of the shoot, the largest being 8 to 10 in. long, 21⁄2 to 31⁄2 in. wide, the smallest 21⁄2 in. long by 1 in. wide; upper surface at first clothed with white down, becoming dark green and less downy with age; lower surface clothed with dense, white felt, like the young shoots. Panicles terminal on the shoots of the current season, 8 to 15 in. long, 1 to 11⁄4 in. wide, densely crowded with very fragrant lavender-coloured flowers arranged in clusters on the main-stalk. Corolla 1⁄3 in. wide across the lobes, 3⁄8 in. long, the tube clothed with white felt outside; calyx 1⁄/6 in. long, with sharp erect teeth, also felted. Blooms in late summer and autumn. Bot. Mag., t. 9564.
Native of Yunnan, China. At Kew it is scarcely hardy enough for the open ground, so is given a place on a wall; if cut to the ground, however, it will grow again from the base and flower from the new growths. It is not so rampant in growth as B. davidii and is allied to B. nivea, but is distinct botanically in having the stamens inserted about the middle of the corolla tube; in B. nivea they are inserted immediately below the mouth.
var. alba Sabourin – Flowers white. These beautiful white-flowered forms of B. fallowiana seem to have arisen early in the twenties in more than one garden where seed of Forrest's sending was raised. Although, like the type, a little tender, they are, in all other respects, finer garden plants than any white-flowered form of B. davidii.
Two buddleias are in commerce which appear to be hybrids of B. fallowiana – perhaps with B. davidii, though this has not been verified. Both originated from the garden of the Earl of Stair at Lochinch, Wigtownshire, and both were originally distributed as typical B. fallowiana. One was put into commerce in the thirties by Messrs Marchant and the other by the Sunningdale Nurseries around 1954. Both are excellent garden plants, hardier and more vigorous than typical B. fallowiana. The hairy coating of the stems and leaves is not so dense as in the species, but sufficient to give to the plants a soft grey-green cast. The two forms differ in that Messrs Marchant's plant has flowers of a lavender blue, borne in erect spikes; in the Sunningdale form, which was named 'Lochinch' in 1959, the spikes droop at the tips and the flowers are of a mauver shade. It is likely that there are other clones of this hybrid in cultivation.