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Scientific: Acanthus mollis
Common: Bear's breeches, oyster plant
Family: Acanthaceae
Origin: Mediterranean region from Portugal and northwest Africa east to Croatia

Pronounciation: A-CAN-thus MOL-lis

Hardiness zones
Sunset
12, 13 (with much protection)-24
USDA 7 (as an annual)-11

Landscape Use: Graceful textural and floral accent, foreground planting, mesic settings with ample water, traditional, old fashioned and nostalgic shade gardens.

Form & Character: Upright and arching, bold, rich, beautiful, regal, old fashioned.

Growth Habit: Evergreen (winter deciduous in colder climates), herbaceous perennial, slowly clumping, about 2- to 3-feet tall when not in flower with equal to greater spread.

Foliage/Texture: Large, deep green glaborous and somewhat with deep lobes and cuts, large to 2-feet long, leaves have pronounced coarse venation and elongated succulent petioles, basal; coarse texture.

Flowers & Fruits: One to several clusters of stalks to heights of 4 feet. Flowers born numerously on stalks. Individual flowers are complex structures up to 2-inches long and surrounded by three green or purplish bracts. The central bract is spiny and is larger than the other two. The flower calyx has two lips - the upper is purple on top, is rather long and forms a kind of "helmet" on top of the corolla. The corolla is reduced to a white lower lip, is tri-lobed with purple-pink venation. The four stamens are fused to the corolla and look like tiny brushes. In all, the flower structure is elegant.

Seasonal Color: Limited to flowering in mid spring (flowers in late spring to early summer along the California coast).

Temperature: In Phoenix, freezes to ground during coldest winters or in colder climates, and sensitive to the most intense desert heat of above 110oF.

Light: Shade

Soil: Prefers a rich, organic and well-drained soil with limited alkalinity.

Watering: Regular and very frequent irrigations in desert areas.

Pruning: Remove spent flower stalks.

Propagation: Division and separation of large tuberous roots.

Disease and Pests: None in Phoenix. In coastal California however, bear's breeches is like ice cream for snails.

Additional comments: Bear's breeches is rarely seen in Phoenix, except in the older, flood-irrigated neighborhoods because of its light anmd heat sensitivities in desert locations. It's definitely not on any of the 'acceptable', water conservation, desert plant lists of desert Arizona municipalities or counties. Otherwise, bear's breeches is a great coarse-textured and large accent plant for large, shaded mesic gardens.

Global perspective: Bear's breeches is an old-fashioned plant commonly found in traditional gardens in many parts of the world. Here is an image of Acanthus mollis growing near Kensington Palace in London, UK.