A semi-herbaceous plant, with erect, branching, annual stems, round, slightly ribbed and hairy, springing from a woody base; the leaflets with scarcely any stalk, obovate, 3⁄4 to 1 in. long, 1⁄8 to 1⁄3 in. wide; hairy, especially beneath. Flower-heads 11⁄2 in. across, produced on hairy stalks 1 to 2 in. long, from the leaf-axils and at the ends of the shoots. Flowers 3⁄4 in. long, six to ten in a head, white; sometimes flushed with pink, calyx 1⁄3 in. long, five-lobed, very hairy. Pod 1⁄3 in. long, glabrous, oblong, containing about four seeds, the calyx persisting at the base.
Native of S. Europe; cultivated in England in 1683. When in bloom it has a resemblance to some brooms of the Cytisus supinus group, but is, of course, very distinct in the smooth pods and axillary inflorescence. It flowers from June to September, and produces seed abundantly; these afford the best means of increase, though the resulting plants will vary somewhat in habit. It is more attractive if grown in a poor soil and hot situation.