thumb|Valerianella locusta illustration by Thomé (1885) showing the plant, flower, and seed
Valeriana locusta, It is a hardy plant that grows to zone 5, and in mild climates it is grown as a winter green.
In warm conditions it tends to bolt to seed, producing much-branched stems with clusters (cymes) of flowers. The flowers have a bluish-white corolla of five fused petals, long and wide, and three stamens. At the base of the corolla is a whorl of bracts. Fertilized flowers produce achenes with two sterile chambers and one fertile chamber.
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Distribution and habitat
Cornsalad grows wild in parts of Europe, northern Africa and western Asia. In Europe and Asia it is a common weed in cultivated land and waste spaces. In North America it has escaped cultivation and become naturalized on both the eastern and western seaboards.
As a cultivated crop, it is a specialty of the region around Nantes, France, which is the primary producer of mâche in Europe.
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History
Cornsalad was originally foraged by European peasants. Jean-Baptiste de La Quintinie, royal gardener of King Louis XIV, introduced it to kitchen gardening. It has been eaten in Britain for centuries and appears in John Gerard's Herbal of 1597. United States president Thomas Jefferson cultivated mâche at his home, Monticello, in Virginia in the early 1800s. mâche ('corn' is used in the sense of 'cereal', not the North American meaning of maize).
In German-speaking Switzerland it is known as Nüsslisalat or Nüssler, terms that have been borrowed by the area's many English speakers. In some areas of Germany it is known as rapunzel, and is the origin of the long-haired maiden's name in the eponymous fairy tale. In restaurants featuring French cuisine, it may be called doucette or raiponce, as an alternative to mâche, by which it is best known. In Croatia and Serbia it is known as matovilac, while in Slovenia it is known as motovilec.
In Spain is known as hierba de los canónigos ("canons' herb") or simply canónigo, a reference to its traditional cultivation in monasteries.
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Nutrition
Cornsalad has a characteristic nutty flavour, dark green colour, and soft texture, and is popularly served as salad greens.
Like other formerly foraged greens, cornsalad has many nutrients, including three times as much vitamin C as lettuce, beta-carotene, B<sub>6</sub>, iron, and potassium. It is best if gathered before flowers appear.