perennial or occasionally biennial with a woody rootstock and flowering stems 10-40cm tall. Basal leaves alternate, oblong to oval, 2-6cm long, l-3cm wide, on tapering stalks about as long as the blade, pinnately lobed, the lobes entire or toothed; the stem-leaves like the basal ones but stalkless. Flowers in dense cymes crowded into an inflorescence up to 15cm long, bluish-purple to white, 5-6mm long by 6-8mm across, the stamens protruding by about 1cm, summer. Mountains of western North America, on rocky slopes. A lovely plant but reputedly difficult, requiring plenty of sun and perfect drainage. Alpine house culture recommended, in lime-free compost. P. sericea subsp. ciliosa has leaves with broader lobes and many fewer silky hairs. The stamens protrude even further.