|Clumping, deciduous perennial, 12 to 18 inches tall and 14 inches wide. Upright green stems bear ovate to elliptic, scalloped, light grayish-green leaves to 3 inches long. Iceberg produces small, white, star-shaped blooms in compact, flat cymes, borne in late summer. These drought tolerant perennials are excellent in rock gardens and borders. Native to China and Korea.