Rock cress is a perennial ground cover for small areas. It works well in rock gardens, along retaining walls, and as an edging plant.
Size and Method of spreading:
Rock cress grows 6 to 12 inches high. It is a trailing-rooting ground cover. Trailing-rooting ground covers have trailing stems that spread out from a central root system. These stems spread out horizontally over the ground and can root where they come in contact with the soil. New shoots will be formed at the point where rooting occurs.
Native geographic location and habitat:
Native to the area around the Mediterranean sea.
The leaves that grow from the base of the plant are obovate and tend to lie flat. The leaves on the stems are lobed and borne alternately. All the leaves have some whitish hairs.
The white flowers are produced in early spring in loose clusters. Each flower has four petals, which is typical of the mustard family. The flowers are fragrant.
Fruit are thin, pod-like silicles and are not ornamentally important.
Rock cress needs full sun and a well-drained soil. Soil can be slightly acidic to alkaline. This plant is drought tolerant, wet soils must be avoided. After flowering, shearing the plants will encourage them to remain neat and compact.
List of pests, diseases, and tolerances:
Root and crown rot can be a problem in wet soils. Aphids and fungal leaf spots are occasional problems. It is resistant to deer.
Snow Cap rock cress (Arabis caucasica ‘Snow Cap’):
Flowers more heavily than the species.