Great butterbur

Petasites japonicus, commonly known as fuki, giant butterbur, or Japanese butterbur, is a robust herbaceous perennial in the family Asteraceae native to East Asia, occurring in Japan, Korea, China, and the Russian Far East along moist streamsides, marsh edges, and damp deciduous forests. The plant arises from a stout, creeping rhizome that produces extensive clonal colonies. Flowering precedes leaf emergence: in early spring, dense clusters of pale yellow-white to greenish disc-flower heads appear at ground level on thick scapes 10 to 25 centimetres tall, surrounded by overlapping pale bracts. The leaves then expand to enormous, round to reniform blades up to 80 centimetres across on stout, fleshy petioles that may reach 1 to 2 metres in cultivated forms, with shallowly toothed or undulate margins, deep green above and lighter beneath. Achenes are linear and bear long silky pappus bristles. It spreads vigorously and is widely cultivated in Japan as the vegetable fuki.