Oyster Plant Acanthus mollis

Bear's breeches is a clumping herbaceous perennial in the Acanthaceae family native to Europe and Africa with large attractive leaves and showy flower spikes. The name Acanthus comes from the Greek word "akantha" which means spine in reference to the toothed edges of the leaves of some members of this genus.  The species name molis means soft hairs. 

The glossy leaves are large and deeply lobed making the plant attractive even when not in bloom. The leaves were used as the model for the Corinthian leaf motif in ancient Greek and Roman architecture. Show stopping spikes of two lipped tublular white flowers with purple hoods appear from late spring to mid-summer and resemble snapdragons.

It grows to 4 feet tall and 2 to 3 feet wide but reaches 5-6 feet tall when in bloom. . The plant spreads by rhizomes and is best grown in an area with root barriers to prevent unwanted spread.  A thick layer of mulch will protect roots from cold winter temperatures. Propagation through root cuttings or division in the early spring but growing from seeds also works.  

Bear's breeches prefers fertile well-drained soils but is tolerant of most soil types except wet ones. It will grow in full sun to partial shade and will do better with some shade in hot climates to prevent leaf scorch. It may go dormant in summer if not irrigated but is drought tolerant once established.

Use this plant in the back of the border, in a container or an area surrounded by pavement like a patio, pool, or walkway. Attractive in small groups, or a single specimen can lend its stately form to an English garden.  The showy flowers work well in a cottage or cutting garden. 

Insects, Diseases, and Other Plant Problems:  Snails and slugs are occasional problems.  Powdery mildew is an occational disease. Be sure to plant it where you want it as it is difficult to get rid of once established.  They can spread aggressively under ideal conditions, root barriers such as those used for bamboo can be used but is shown to be invasive in some areas of the US.