Arabis L.

Rock Cress

Greek Arabis—Arabia.

Annual, biennial or perennial herbs. Hairs unbranched, forked, stellate or absent. Leaves simple, entire sometimes lobed or toothed. Flowers in terminal clusters; sepals and petals 4, the inner sepals bagged at the base; petals mostly white, occasionally pink or purple. Fruit a siliqua with flat valves; seeds in one row in each chamber and often winged.

Often mat-forming, grown as edging plants and in rock gardens etc, generally in cool-climate areas; the species and cultivars grown in southeastern Australia require taxonomic investigation.

Cultivars are probably the result of hybridisation and may be difficult to assign to a species.

A. blepharophylla Hook. & Arn. from C California is occasionally offered; it has fragrant rosy purple flowers, oblong to spoon-shaped, toothed or entire leaves, and fruits 2.5-4 cm long; the white-flowered A. alpina L. and the white-flowered and grey-leaved A. caucasica Schlechtend. are also sometimes offered, both have toothed leaves.

Division, seeds or cuttings.

Fruit usually more than 4 times as long as wide, valves nerved, soon shed; sepals not overlapping.

About 120 species, mostly northern temperate from N America and Eurasia to tropical Africa.

Source: Spencer, R. (1997). Brassicaceae. In: Spencer, R.. Horticultural Flora of South-eastern Australia. Volume 2. Flowering plants. Dicotyledons. Part 1. The identification of garden and cultivated plants. University of New South Wales Press.

kingdom Plantae
phylum   Tracheophyta
class    Magnoliopsida
superorder     Rosanae
order      Brassicales
family       Brassicaceae
Higher taxa
Subordinate taxa
species         Arabis caucasica Schltdl.