Petasites japonicus var. giganteus

Fuki or Giant Japanese Butterbur Asteraceae

If Petasites japonicus is impressive, var. giganteus is what happens when someone forgets to install the size limiter. The Japanese Akitabuki or Giant Butterbur produces enormous, rhubarb-like leaves, potentially approaching 1.5m across, on stout stalks, creating a wonderfully prehistoric effect in damp shade. It is native particularly to northern Japan, Hokkaido and Tohoku, extending into Sakhalin and the southern Kuriles. 

There is a culinary tradition behind all this foliage. In Japan, young leaf stalks and the emerging flower heads (‘fuki-no-tō’) are harvested as a spring vegetable. The stalks are traditionally blanched or boiled, peeled and seasoned, pickled or cooked with miso; the flower buds are commonly prepared as tempura or used as a flavouring. 

Important: butterbur contains pyrrolizidine alkaloids, so it should not be eaten raw; traditional preparation is intended to reduce bitterness and remove some compounds, but does not make the plant risk-free. 

A superb plant for pond margins, streamsides and very damp woodland, but give it room—or confine it to a large container—as its vigorous rhizomes can make it an enthusiastic traveller.

Height: 1–2m | Spread: 1–2m+
Flowering: February–April | Foliage: Deciduous
Hardiness: H5 (-15 to -10°C)