Basil Soapwort Saponaria ocymoides

Rock Soapwort is a flowering, evergreen, herbaceous perennial, subshrub in the carnation family and native to mountainous slopes of Spain and central Europe. It spreads low to the ground, densely branched, and maturing in 2 to 5 years to a mat 9 inches high with a spread of 2 feet, making it ideal as a ground cover. The leaves are greyish green and the flowers appear as a carpet of pink in summer. The genus name comes from the Latin word sapo meaning soap. The species name means "resembling basil" referring to either the shape of the leaves or the highly branched habit.

Rock Soapwort prefers well-drained, medium to dry, slightly alkaline, loamy soil, but tolerates light-textured soil. Plant in full sun to maximize blossoms. Once established, it will also tolerate some drought. This plant will self-seed in the garden, but is not considered aggressive. It is hardy across Zones 2-9, but may have problems with hot, humid summers or with wet roots in winter. After flowering, you can prune the plant back by half to encourage branching, bushy growth and reblooming. You propagate the plant by dividing the clumps in spring or summer.

This plant works well in a rock garden, containers (if spread is an issue), border edges, or trailing over a rock wall. You can plant Rock Soapwort between stepping stones, but it does not tolerate heavy foot traffic. When planting, space plants 10 to 16 inches apart.

Diseases, Insect Pests, and Other Plant Problems:

No known diseases or insect pests. May be susceptible to slugs and snails.