An evergreen shrub of low growth; shoots glabrous, terete, reddish, thornless. Leaves elliptic-lanceolate, or narrowly oval, 2 to 5 in. long, 3⁄8 to 1 in. wide, strongly armed with stiff marginal teeth; stalkless, shining pale green beneath, borne singly and alternately on young shoots and in axillary clusters on older wood. Flowers 3⁄8 to 1⁄2 in. across, bright yellow, borne in short-stalked, dense clusters of fifteen to thirty; petals obovate. Fruit 'grape purple'.
Native of N. Burma, discovered by Kingdon Ward and introduced in 1931. It is a handsome foliage shrub belonging to the Wallichianae group and shows relationship with B. insignis, especially in the unarmed shoots. The foliage is particularly interesting for the pale green of the under-surface. It was first distinguished in the collection at Wisley but is not now in cultivation there. The specific name refers to the curious thickening upwards of the flower-stalks.
From the Supplement (Vol. V)
This now ranks as a subspecies of B. insignis – subsp. incrassata (Ahrendt) D. Chamberlain & C. M. Hu.