|Hardy and strong rhizome producing perennial with simple, toothed, lance-shaped dark green leaves. Reaches 24 inches tall. From early summer to fall, flowerheads form loose corymbs to 4 inches across in white. 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.