|Hardy and strong rhizome producing perennial with simple, toothed, lance-shaped dark green leaves. Reaches 18 to 24 inches tall. From early to late summer, double flowerheads in pure white form loose corymbs to 4 inches across. This heat and drought tolerant perennial has a fiberous root system and can become invasive. Divide to maintain. Butterflies are attracted to this plant. Good cut flower that dries well, too. Sometimes referred to as Achillea ptarmica 'Boule de Neige'.