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Basil Soapwort

Saponaria ocymoides (sap-oh-NAIR-ee-ah ok-ee-MOY-deez)

Family: Caryophyllaceae Non-native Groundcover (<1 ft)

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.

Source: NC State Extension Gardener Plant Toolbox ↗ NC State Extension Gardener Plant Toolbox, 53 attributes.

How it fits the guild

Guild layer 5 - Groundcover (<1 ft) Optimal soil pH Alkaline (>8.0); Neutral (6.0-8.0)
See companions & conflicts ↓

Companions & Conflicts

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.

Full plant profile

Growing Conditions
Plant type
Ground Cover; Herbaceous Perennial; Shrub
Life cycle
Perennial
USDA zones
2a, 2b, 3a, 3b, 4a, 4b, 5a, 5b, 6a, 6b, 7a, 7b, 8a, 8b, 9a, 9b
Light
Full sun (6 or more hours of direct sunlight a day)
Soil texture
Loam (Silt); Sand
Soil pH
Alkaline (>8.0); Neutral (6.0-8.0)
Soil drainage
Good Drainage | Occasionally Dry
Available space
12 inches-3 feet
NC region
Mountains; Piedmont
Mature size
Height: 0 ft. 6 in. - 0 ft. 9 in. | Width: 1 ft. 0 in. - 2 ft. 0 in.
Growth rate
Medium
Maintenance
Low
Canopy layer
5 - Groundcover (<1 ft)
Form & Appearance
Habit / form
Dense; Mounding; Spreading
Texture
Medium
Foliage
Broadleaf Evergreen
Leaf color
Gray/Silver; Green
Leaf arrangement
Opposite
Leaf shape
Lanceolate; Ovate
Leaf margin
Entire
Leaf size
1-3 inches long, < 1 inch wide
Hairs present
Yes
Leaf detail
Teardrop-shaped leaves up to 1 inch long and a half inch wide, close to the stems, and greyish-green in color.
Flower color
Pink; Purple/Lavender
Flower value
Long Bloom Season; Showy
Flower form
Cyme
Flower shape
Radial
Flower size
< 1 inch
Flower detail
Bright purplish, five petaled, pink flowers blossom May to August in small sprays of 1/2 to 1 inch in diameter. The bloom period can last up to three weeks.
Bloom time
Spring; Summer
Fruit type
Capsule
Stem color
Red/Burgundy
Stem detail
The trailing red stems can be semi-woody.
Wildlife & Ecology
Native status
Non-native
Origin
Spain, South West and South Central Europe.
Distribution
Introduced into Britain, Sweden, Denmark, New England, New York, and some western states.
Food & Medicine
Fruit type
Capsule
Landscape Use
Landscape location
Container; Lawn; Rock Wall; Slope/Bank
Landscape theme
Drought Tolerant Garden; Rock Garden
Design feature
Border; Foundation Planting; Mass Planting
Garden tags
#evergreen #mounding #herbaceous perennial #groundcover #trailing #broadleaf evergreen #showy flowers #drought tolerant #clumping #division #subshrub #vigorous
Problems & Resistance
Insect problems
Slugs and Snails Found on Flowers and Foliage
Resistant to
Deer; Drought; Poor Soil
Propagation
Division; Seed

Planted at Hunnicutt

Nobody’s planted this one yet.