The hardy perennial Arabis typically flowers in the early spring.
Rock and Wall Cress are small plants that are often mat forming.
They have scented white flowers and are useful plants for growing in rockeries.
Arabis photograph by nociveglia.
Arabis Flower (Lyre-leaved Rock Cress) by Wackybadger.
Arabis-alpina (Alpine Rock-cress), photograph by Alastair Rae; CC.
Arabis lyrata (Lyre-leaved Rock Cress), picture by Joshua Mayer; CC.
It is best to sow out Arabis species on the soil surface, following germination they can be thinned out with a spacing of approximately thirteen to thirty centimeters (12 inches).
Rock cress should be sown out in the early spring when a light frost is still possible or in the late autumn. They require the vernalisation process to flower.
The plants prefer to be grown in full sunlight, but are quite hardy and therefore tolerant to light shady conditions.
The soil type is not overly important, but it should be well drained. Ideally the soil should (though not essentially) have a pH of 5.5 to 7.
When starting Arabis off from seed indoors, the seeds should be started six to eight weeks before planning to plant out in peat pots. They can then be pricked out in the Early Spring.
Arabis are very easy to look after. The plant should be deadheaded following flowering to prevent self fertilization, and to maintain a neat appearance.
A genus closely related to Arabis is the Arabisdopsis genus, (Brassicaceae family); the annual Arabidopsis thaliana, is one of the most used plants in biological research. It is a model species, has five chromosomes, and has been fully sequenced. Research into the plant has led to a great increase in the understanding of how a plant functions.