A deciduous shrub about 2 ft high, of lax, pendulous growth; young shoots slender, four- or five-angled, glabrous, green. Leaves linear, pointed, glabrous or almost so, 3⁄8 in. long, 1⁄16 in. wide, set about half an inch apart. Flowers produced three or four together towards the end of short lateral twigs in May and June, bright yellow, 3⁄8 in. long, standard petal 1⁄4 in. wide; calyx glabrous, 1⁄12 in. long, tubular, with five narrowly triangular, pointed, erect lobes. Pods about 1 in. long with a short bristle at the end, containing one to five seeds. Bot. Mag., n.s., t. 292.
A native of the E. Balkans and western Asia Minor; introduced in 1926 by the late Dr Turrill by means of seeds collected by him in the Rodopi massif in Bulgaria, on limestone rocks above Bačkovo. The merits of this beautiful shrub were soon appreciated and since World War II it has become common in gardens. In a sunny, well-drained position it is quite hardy in the sense that it will withstand low winter temperatures. The sudden death of branches or whole plants may be the belated effect of hard early winter frosts after a rainy mild autumn, or of late spring frosts. It is best suited to a ledge in a large rock garden or the top of a dry wall, where its graceful habit can show to best advantage. But more compact plants can be obtained by light pruning as soon as the flowers are over.
G. lydia is allied to G. januensis, but that species (q.v.) differs in its broader leaves and triangular stems. Also, G. januensis has a more northern and western distribution, though intermediates may occur.