Spiny bear’s breeches is a clumping perennial plant in the Acanthaceae (acanthus) family. It is native to Europe and the Mediterranean. The Greek word akantha means spines which refers to the toothy edges some leaves in the genus. Spinosus means spiny and comes from the stiff spines found on the margins of the leaves that resemble that of the thistle. This plant prefers well-drained soil in partial shade, with some protection from the afternoon sun in our hot southern climates. While it grows in a wide variety of soils it does not do well in wet soils. Slow growing, it can take some time to establish but once it takes hold, it spreads easily by seed and root cutting, making it almost impossible to eradicate out of a planting bed. Its showy spikes of purple-white flowers that resemble snapdragons bring a pop of color to shady spots and make attractive additions to cut-flower bouquets. The large, spiky, arching leaves should not be ignored as they are what inspired the design of Greek Corinthian columns. Use bear’s breeches as an accent or border plant in the landscape or in a cutting garden. Insects, Diseases, and Other Plant Problems: Slugs and snails can do damage.
Curated pairwise relationships between this plant and others in the library — who feeds
whom, who competes, who confuses the pests. Green reads as a good pairing, red as one to avoid.
No curated interactions recorded for this species yet.
Also noted by NC State
Related species the NC State Plant Toolbox flags for this plant — look-alikes to tell
apart, and plants that play a similar role in a planting. Ones we carry in the library are linked.
Partial Shade (Direct sunlight only part of the day, 2-6 hours)
Soil texture
Clay; High Organic Matter; Loam (Silt); Sand
Soil drainage
Good Drainage
Available space
3 feet-6 feet
NC region
Coastal; Mountains; Piedmont
Mature size
Height: 3 ft. 0 in. - 4 ft. 0 in. | Width: 3 ft. 0 in. - 4 ft. 0 in.
Maintenance
Low
Canopy layer
4 - Herbaceous (3-15 ft)
Form & Appearance
Habit / form
Clumping; Creeping; Erect; Spreading
Texture
Coarse
Foliage
Deciduous
Leaf color
Green
Leaf type
Simple
Leaf arrangement
Rosulate
Leaf margin
Lobed
Leaf feel
Glossy; Prickly
Leaf value
Long-lasting; Showy
Leaf size
> 6 inches long, > 6 inches wide
Hairs present
No
Leaf detail
Bear's breeches colorful deeply cut leaves make a bold architectural statement with its large (2'-3'), spiny leaves, which served as the pattern for the design on Greek Corinthian columns. They are arching, glossy, thistle-like leaves that emerge from a rosette in the center of the plant.
Flower color
Pink; Purple/Lavender; Red/Burgundy; White
Flower value
Good Cut; Showy
Flower form
Spike
Flower shape
Irregular; Lipped; Tubular
Flower size
1-3 inches
Flower detail
White snapdragon-like flowers surrounded by spiny pink-mauve-red bracts arranged in rows on showy spikes that are 3-4' tall. Blooms late spring to mid-summer.