| Scientific Name: | Petasites japonicus |
| Common Name: | giant butterbur |
| Family Name: | Asteraceae |
| Origin: | S.E. Asia / Japan / China |
| Hardiness Zone: | Zone 5: (-29 to -23 °C) |
| Plant Type: | Herbaceous perennial |
| Mature Size: | 0.7 - 1.3m x 0.6 - 1.0m (height x width) |
| Habit: | Arching |
| Form: | Vase |
| Texture: | Very coarse |
| Landscape Uses: | Waterside planting, Wetland - bogs |
| Exposure: | Full sun only if soil kept moist, Part sun/part shade, Filtered shade |
| Soil or Media: | Bog |
| Leaves: | Simple, Basal, Leathery, Palmate venation, Tomentose, Reniform, Serrate |
| Flowers: | Head (capitulum), White, Green-yellow, Mar-Apr |
| Fruit: | Cypsela (achene + calyx), White, Silver, May |
| Key ID Features: | |
| Leaves large, basal, and rounded (up to 80cm wide for P. var. gigantum); florets yellowish-white, fragrant, in daisy-like heads arranged in corymbs that appear in April before the leaves emerge from the soil. | |