Petasites hybridus

RHS Plant Profile

butterbur

Other common names

batter dock, bog rhubarb, butter dock, cleats, cleets, flea dock, gallon, oxwort, pestilence wort, poison rhubarb, son-before-the-father, umbrella leaf, water docken, alan mawr

Synonyms

Petasites officinalis
Petasites vulgaris
Tussilago hybrida

Herbaceous Perennial

A perennial native with dense, cylindrical clusters of pinkish flowers on sturdy, upright stems, appearing in early spring before the foliage. Can form large colonies, spreading via fleshy rhizomes, with heart-shaped leaves up to 1m across felted white on the undersides

Position

Full shade, Full sun, Partial shade

Soil Types

Clay, Loam

Max Height

1-1.5 metres

Max Spread

2.5-4 metres

Size

Time to Maturity: 5–10 years
Max Spread: 2.5-4 metres
Max Height: 1-1.5 metres

Growing Conditions

Clay Loam

Moisture: Moist but well–drained or Poorly–drained
pH: Acid or Alkaline or Neutral

Position

Full shade Full sun Partial shade

Aspect: East–facing or North–facing or South–facing or West–facing
Exposure: Exposed or Sheltered
Hardiness

Hardiness Ratings

All ratings refer to the UK growing conditions unless otherwise stated. Minimum temperature ranges (in degrees C) are shown in brackets

H1A: under glass all year (>15C)
H1B: can be grown outside in the summer (10 - 15)
H1C: can be grown outside in the summer (5 - 10)
H2: tolerant of low temperatures, but not surviving being frozen (1 to 5)
H3: hardy in coastal and relatively mild parts of the UK (-5 to 1)
H4: hardy through most of the UK (-10 to -5)
H5: hardy in most places throughout the UK even in severe winters (-15 to -10)
H6: hardy in all of UK and northern Europe (-20 to -15)
H7: hardy in the severest European continental climates (< -20): H5

Colour & Scent

Season	Stem	Flower	Foliage	Fruit
Spring
Summer
Autumn
Winter

Botanical Details

Family: Asteraceae
Native to GB/Ireland: Yes
Foliage: Deciduous
Habit: Bushy, Matforming
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

How to Grow

Cultivation

Prefers wet soil and partial shade, occuring naturally in damp fields and woods, or along streamsides and ditches. Develops from a strong network of rhizomes, and can be useful to stabilise sloping ground, but may swamp other plants and need to be controlled in gardens. See butterbur and winter heliotrope for more information

Propagation

Divide in spring

Suggested planting locations and garden types

Wildlife gardens
Banks and slopes

Pruning

No pruning needed but can remove old foliage once it dies down

Pests

Generally pest-free

Diseases

Generally disease-free