A shrub about 2 ft high, but twice as much in diameter, forming a low mound of tangled, slender, spreading branches, densely clothed with grey, partly starry down. Leaves narrowly obovate or oblong to ovate-lanceolate, mostly tapered at the base, rounded or blunt at the apex, 1⁄3 to 11⁄4 in. long, 1⁄8 to 1⁄2 in. wide, grey with a dense down. Flowers in a branched, terminal hairy corymb; each flower 11⁄2 to 13⁄4 in. diameter, bright yellow, unblotched. Sepals three, ovate, pointed, densely but shortly hairy, 1⁄3 in. long; flower-stalk thickening upwards.
Native of the north-western part of the Iberian peninsula, and also of western and central France, where it extends east as far as the Massif Central and north to the region of Le Mans and Orleans; in cultivation 1775. It is allied to H. lasianthum but differs in having shorter hairs on the sepals and pedicels, in the absence of purplish bristles on the calyx, and in the always unspotted petals. The low, spreading form described above is not reliably hardy, but the species has such a wide north-south range that it is likely to vary in hardiness, as it certainly does in habit, some wild plants being erect-branched and up to 3 ft high. Also, the plant described above, having the leaves grey and hairy above, probably came from the southern part of the area of the species. More commonly, H. alyssoides has the leaves green above.