Petasites japonicus
giant butterbur
P. japonicus is a substantial plant, producing huge suborbicular leaves to 90cm across, reaching 150cm in height, in summer. Flowers are cream to white, borne in February on stout erect stems to 30cm. The plant normally available is nearly always the male plant
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Size
Ultimate height
1–1.5 metresTime to ultimate height
2–5 yearsUltimate spread
4–8 metresGrowing conditions
Moisture
Moist but well–drained, Poorly–drainedpH
Acid, Alkaline, NeutralColour & scent
| Stem | Flower | Foliage | Fruit | |
| Spring | Cream White | |||
|---|---|---|---|---|
| Summer | Green | |||
| Autumn | ||||
| Winter |
Position
- Full shade
- Partial shade
Aspect
North–facing or East–facing
Exposure
Sheltered Hardiness
H6Botanical details
- Family
- Asteraceae
- Native to the UK
- No
- Foliage
- Deciduous
- Habit
- Bushy
- Genus
Petasites are perennial plants, usually large, with thick rhizomes or stems. Leaves are often very large and either heart-shaped or kidney-shaded. Scapes or stems many-headed, with any leaves usually reduced to scales. Flowers dioecious in usually rayless heads, purple or white, rarely yellowish, borne in panicles or racemes at the ends of the scapes
- Name status
Correct
- Plant range
- Korea China Japan
How to grow
Cultivation
Grow in deep humus-rich, fertile soil that is permanently moist but not stagnant, in partial or full shade. It may become invasive
Propagation
Divide in spring
Suggested planting locations and garden types
- Wildlife gardens
- Low Maintenance
Pruning
Remove the old foliage before the onset of new growth in late winter
Pests
Generally pest-free
Diseases
Generally disease-free
Get involved
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