Common Name: butterbur
Type: Herbaceous perennial
Family: Asteraceae
Native Range: Korea, China, Japan
Zone: 5 to 9
Height: 2.00 to 3.00 feet
Spread: 2.00 to 5.00 feet
Bloom Time: April
Bloom Description: Yellowish-white
Sun: Part shade to full shade
Water: Medium to wet
Maintenance: Medium
Suggested Use: Water Plant, Vegetable, Naturalize, Rain Garden
Flower: Showy, Fragrant
Tolerate: Heavy Shade, Erosion, Wet Soil
Culture
Easily grown in consistently moist to wet soils in part shade to full shade. If grown in full sun, leaves will typically wilt during hot days in somewhat the same manner as with the ligularias. Best grown at the shoreline of large natural ponds, on the banks of streams or in bogs. Tolerates a wide range of soils as long as consistent moisture is present. Large containers sunk in the mud may be used if control of rhizomatous spread is desired. Grow in containers for water gardens or smaller ponds.
Noteworthy Characteristics
Petasites japonicus, commonly known as butterbur, fuki or sweet coltsfoot, is a rhizomatous perennial that is noted for its huge basal leaves that form dense spreading clumps of foliage to 3’ tall and 5’ wide. It is native to Korea, China and Japan where it is typically found growing on wet streambanks in woodland areas. Long-stalked, lightly toothed, kidney-shaped, green leaves (to 16-32” wide) are tomentose beneath. Fragrant, yellowish-white, daisy-like flowers in dense corymbs appear in spring before the leaves emerge on rigid scapes to 6” tall. Scapes elongate after bloom. Leaf stalks (petioles) are eaten as a vegetable (fuki) in Japan.
Genus name comes from the Greek petasos meaning a hat with a broad brim with reference to the large leaves.
Specific epithet means of Japan.
The leaves were reportedly once used to wrap butter in hot weather, hence the common name.
Problems
No serious insect or disease problems. Watch for slugs. Spreads aggressively by rhizomes if not grown in containers or otherwise restrained by barriers.
Uses
Banks of ponds, streams or water gardens. Bogs. Shady corner of the border or woodland garden as long as the soil moisture requirements can be met.