These twiggy, low-growing shrubs make fine bank or ground covers and are a welcome addition to the rock garden. Good drainage is essential for their survival; they grow well in sandy or gravelly, infertile soils. Showy, sweet pea shaped yellow flowers appear in spring. Leaves are often small and short lived; green branches give deciduous sorts an ever- green look.
G. lydia. Zones US, MS, LS; USDA 6-8. Evergreen; nearly leafless. Grows to 2 ft. tall and 3 ft. wide; makes a good ground cover. Profuse show of blossoms at tips of shoots in late spring. Sets few seeds.
G. pilosa. Zones US, MS; USDA 6-7. SILKYLEAF WOADWAXEN. Deciduous. Fairly fast-growing prostrate shrub, ultimately to 1112 ft. tall with 7-ft. spread. Intricately branched gray-green twigs; roundish, 14- to 1-in.-long leaves. Blooms in spring. 'Vancouver Gold' is a good selection.
G. tinctoria. Zones US, MS; USDA 6-7. DYER'S GREENWEED, WOADWAXEN. Deciduous. To 6 ft. tall and wide, with undivided leaves to 2 in. long. Upright flower spikes in late spring or early summer. 'Royal Gold' is a compact selection 2 ft. tall and wide.