Acanthus spinosus L.

RHS Plant Profile
spiny bear's breech

Other common names

armed bear's breech, spiny bear's breeches

Synonyms

Acanthus caroli-alexandri

Herbaceous Perennial

A handsome herbaceous perennial to 1.2m, with large, deeply lobed and spine-tipped, dark glossy green leaves. Erect spikes of white flowers with spiny purplish bracts in late spring and summer

Position

Full sun, Partial shade

Soil Types

Chalk, Loam, Sand

Max Height

1-1.5 metres

Max Spread

0.5-1 metres

Size

Time to Maturity
2–5 years
Max Spread
0.5-1 metres
Max Height
1-1.5 metres

Growing Conditions

Chalk Loam Sand
Moisture
Well–drained
pH
Acid or Alkaline or Neutral

Position

Full sun Partial shade
Aspect
South–facing or North–facing or West–facing or East–facing
Exposure
Exposed or Sheltered
Hardiness
H6
Drought Resistance
Yes

Colour & Scent

Season Stem Flower Foliage Fruit
Spring
Summer
Autumn
Winter

Botanical Details

Family
Acanthaceae
Native to GB/Ireland
No
Foliage
Deciduous
Habit
Columnar upright
Genus
Acanthus are robust herbaceous perennials with handsome, lobed foliage and tall, erect racemes of two-lipped flowers with colourful bracts
Name Status
Correct
Plant Range
Mediterranean

How to Grow

Cultivation

Grow in sun or part shade, will tolerate most soils but thrives in deep loam. Acanthus need careful positioning as they can be difficult to remove once established. Has the potential to become a nuisance if not managed well

Propagation

Propagate by division or by root cuttings

Suggested planting locations and garden types

  • Cottage and informal garden
  • Mediterranean climate plants
  • Architectural
  • Low Maintenance
  • Cut flowers
  • Flower borders and beds

Pruning

Cut down old flower stems

Pests

Generally pest-free

Diseases

May be susceptible to powdery mildews