Arabis is a genus of flowering plants belonging to the family Brassicaceae. The species in this genus tend to vary greatly. They are either perennial, meaning they live for at least two years, or herbaceous, which means they die at the end of each growing season. Most species are quite short and have a large amount of hair on them. They bear long, capsule-shaped fruit that have 10 to 20 seeds in them.
This genus has more than a 100 species that are endemic to the desert, which is why its name is derived from the country Saudia Arabia. Out of the many species, some are considered ornamental plants, while others are considered weeds. A popular species, Arabis alpina, is regarded as an ornamental plant and found in Europe, North Africa, and North America. This plant grows to a height of about 1.3 feet (40 cm), and the flowers are white and four-petaled. As of 2010, Arabis alpina is being considered for selection as a model organism for a population genetics study.
Yet another species, Arabis glabra, commonly known as tower mustard, is a tall plant with small, off-white flowers. It is widespread in Asia, Europe, and Africa, though it is considered in danger of becoming extinct in the United Kingdom. The tower mustard is seen in wide, open places with little soil.
Another species of Arabis is caucasica, which is found in southeastern Europe. Also known as the rockcress, it has leaves that are edible and used for garnishing purposes. It is a perennial plant with a maximum height of 3 feet (1 m). Some species, like A. caucasica, bear white flowers, while others have red, purple, or pink colored flowers. Each flower consists of four sepals and four petals.
In order to flourish, the A. caucasica plant requires very little water, but plenty of sunlight. Harsh temperatures are tolerated with ease, and it can survive in below zero climates without withering away. For best results, the plant should be grown outdoors.
Wallcress and rockcress are tough plants that require very little care, and they can grow in scanty sunlight or survive in drought-like conditions. To allow optimum growth, plant them in balconies and terraces where they can hang over an open area. They have small flowers that completely cover the plant and attract butterflies. All rockcresses are edible and possess a sharp flavor similar to mustard. The stems, leaves, and flowers are used to dress up salads, soups, and sandwiches.