Rhizomatous plant that forms dense clumps, robust in appearance. The leaves are acinate, long and erect (up to 1 m high and 1-2 cm wide), perennial, light green. It forms flowers up to 6 cm in diameter, pale yellow with dark spots, which grow at the end of the flowering branches. The flowers last only a few days but as the bush has abundant flower buds, it is seen in bloom from late spring and throughout the summer. The flowers attract numerous insects which, in turn, attract insectivorous birds.