Epilobium parviflorum

RHS Plant Profile
hoary willowherb

Other common names

helyglys lledlwyd

Herbaceous Perennial

A native perennial to about 75cm tall. Often overwintering as a rosette of leaves, it has upright, leafy stems covered in fine hairs. Small, pale pink flowers in summer have long, tubular ovaries, developing into pods that burst open to release seeds dispersed with the help of silky parachutes

Position

Full sun, Partial shade

Soil Types

Clay, Loam

Max Height

0.5-1 metres

Max Spread

0.1-0.5 metres

Size

Time to Maturity
2–5 years
Max Spread
0.1-0.5 metres
Max Height
0.5-1 metres

Growing Conditions

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

Position

Full sun Partial shade
Aspect
East–facing or North–facing or South–facing or West–facing
Exposure
Exposed or Sheltered
Hardiness
H7

Colour & Scent

Season Stem Flower Foliage Fruit
Spring
Summer
Autumn
Winter

Botanical Details

Family
Onagraceae
Native to GB/Ireland
Yes
Foliage
Semi evergreen
Habit
Clump forming
Genus
Epilobium can be annuals or perennials, sometimes invasive, with erect stems bearing willowy leaves and showy, 4-petalled flowers in terminal racemes
Name Status
Correct

How to Grow

Cultivation

Naturally found in wet or damp soils, but can stray into gardens. Worth tolerating to increase biodiversity and as a food plant for caterpillars of elephant hawkmoth, and other moth species. See willowherbs for more information

Propagation

Spreads readily by windborne seed

Suggested planting locations and garden types

  • Wildflower meadow
  • Wildlife gardens

Pruning

No pruning required; deadheading will reduce self seeding

Pests

Generally pest-free

Diseases

Generally disease-free, but may be susceptible to rust diseases and powdery mildews