A dwarf shrub, forming a compact tuft rarely more than 6 in. high, but 1 ft or more in diameter; young stems and leaves covered with a short down and a few hairs. Leaves without stipules, hairy and green above, grey beneath with stellate down, ovate-oblong, 1⁄4 to 3⁄4 in. long. Flowers in terminal cymes, sometimes a panicle, usually of three to six blooms, each 1⁄2 in. across, bright yellow, un-blotched. Sepals five, hairy, the two outer ones very small. Seed-vessel thickly hairy.
Native of Europe, Asia Minor, and the Caucasus, found in a few stations in the British Isles, mostly on limestone (Yorkshire, Cumberland, Westmorland, N. Wales, Glamorgan; and Galway and N. Clare in Ireland). It is hardy, and makes a pleasing little tuft for the rock garden when covered with its brightly coloured flowers. From the other British species, except the herbaceous H. guttatum (Tuberaria guttata), it differs in having no stipules. With the non-native species cultivated in gardens it is only likely to be confused with H. alpestre, which also has no stipules, but whose leaves are green on both surfaces. Botanists also rely on the longer, oval and pointed flower-buds of H. alpestre, in contrast to the globose ones of the present species.
H. canum is a rather variable species, with local variants that differ somewhat in indumentum, leaf-shape, or inflorescence from the plant described above, which belongs to the typical subspecies. Six others are described in Flora Europaea.