Stephen Albert
Arabis, commonly called wall rockcress, is a small mounding plant covered in white blossoms in early to mid-spring. Wall rockcress is a colorful addition for rock gardens and rock walls and containers.
Rockcress is a genus of annuals, biennials, and perennials of the Mustard Family including delightful, low-growing border and rock-garden plants of easy culture.
Reaching heights of from 6 to 12 inches (15-30cm), they bear a profusion of white, pink, or purple flowers in early spring to early summer. They prefer a sunny location but will get along in partial shade.
Given a light, sandy soil enriched with bone-meal worked in around each plant when it is set out, these charming plants produce an abundance of blossoms and attractive mats of foliage later in the season after the blossoms.
Seed may be sown out of doors in mid to late spring; it should be covered to a depth of twice its diameter. Mixing a little sand with the seeds will facilitate even sowing.
Get to know Arabis
- Plant type: Perennial
- Growing Zones and range: 4-7
- Hardiness: Rockcress will languish in warmer zones
- Height and width: 6 to 10 inches (15-25cm) tall; 12 to 18 inches (30-45cm) wide
- Form: Evergreen groundcover 4 to 6 inches high; 1-inch leaves are clothed in soft hair and are often obscured by flowers.
- Flower form: mounds of white, pink, or rose-purple blossoms
- Bloom time: Late winter to mid-spring
- Uses: Rock garden, creeping over walls, interplant with spring bulbs
- Garden companion: False rockrose, daffodils
- Common name: Wall Rockcress
- Botanical name: Arabis caucasica and species
- Family: Brassicaceae
Where to plant Arabis
- Plant Arabis in full sun.
- Arabis will grow in good to poor, loose, well-drained soil. Rockcress tolerates a wide range of soil moisture and fertility.
When to plant Arabis
- Set Arabis starts or divisions in the garden in spring.
Planting and spacing Arabis
- Space Arabis 12 to 18 inches (30-45cm) apart.
- Sow seed in spring; sow seed 1/8 inch deep in evenly prepared soil.
How to water and feed Arabis
- Keep the soil just moist for Arabis.
- It is not necessary to fertilize Arabis.
Arabis care
- Mulch around Arabis in summer to keep the soil and root cool.
- Spraying with bordeaux mixure every 10 days from mid-spring to early autumn will keep plant healthy.
Arabis propagation
- Divide Arabis every 2 to 3 years. Divide in spring or fall.
- Take cutting in spring.
- Plants can be started by layering; bury 6 inches of low-growing stem and leave the leafy tip exposed.
- Sow seed in spring; sow seed 1/8 inch deep in evenly prepared soil.
Arabis pests and diseases
- Hot, humid, or wet climates encourage root or crown rot.
- Cut back stems after flowering to keep plants tidy and to encourage new blooms.
Arabis varieties to grow
- Some cultivars are double-flowered.
- ‘Pink Charm’ and ‘Rosabella’ have pink flowers.
- ‘Snow Cap’ has profuse white flowers.
- Arabis aplpina,mountain rockcress: low tufted plants to not more than 10 inches high; white flowers in dense clusters; cultivar ‘Rosea’ has pink flowers.
- A. blepharophylla, rose cress, California rockcress: low-growing tufted plant with rose-purple flowers; use in rock gardens or containers.
- A. caucasica: wall rockcress is a popular variety; gray leaves; white flowers almost cover the plant in spring; use as a base for flowering bulbs; cultivar ‘Variegata’ has white flowers and silvery leaves edged in white.
- A. procurrens: creeping plant with white flowers tolerates light shade.
