is the most widespread of three species of this non-native genus to have become established in the US. Stems are tall, erect, and branched (mostly towards the base), bearing large leaves at alternate intervals; these can be over 2 feet long at the base, becoming gradually smaller up the stem. Leaf margins are usually irregularly and shallowly toothed. Leaves have prominent, light-colored veins. Leaf bases are heart-shaped.
The spherical, thistle-like flowerheads are produced in small clusters at the top of the stem, subtended by a few leafy bracts. Flowerheads consist of many rows of recurved, linear, hooked phyllaries, hairy or hairless, below several dozen disc florets, colored purple to pink. The disc corollas are tubular, opening to four triangular lobes from which projects an exserted, white-purple style topped by a branched stigma.