A herbaceous perennial, it grows 4 ft (120 cm) high, with fern-like foliage. The leaves are linear, pinnate, lobed and serrated, hairy and rough. The flowers are arranged in corymbs, or panicles, of a complex character; they are very large, often 5 in (13 cm) across. The smaller corymbs are arched or convex, causing the cluster or compound corymb to present an uneven surface. In the species the small flowers are of rich 'old gold' yellow colour, and are very rigid, almost hard. The flowering period is mid to late summer.[