The plant has one simple erect stem, which is green with purple dots or longitudinal dashes and can grow over six feet tall. The upper stems are reddish or purplish. Leaves and primary subdivisions of the flower head appear in whorls of 3–5 (rarely 2 or 6, the rotational symmetry of most plants is consistent). Leaves are large, long and sharply toothed. One plant can produce several flower heads in a branching array, each head with 4-7 pink or purple disc flowers but no ray flowers