Allium schoenoprasum, known as chives, is a perennial monocot in the onion genus. It is the smallest species of the edible onions, and is the most widely distributed—it is only Allium species that is native to both the New and the Old World, found in Europe, Asia, and North America and growing in arctic regions up to 70° N latitude or in mountainous regions at lower latitudes (Brewster 1994). The name of the species derives from the Greek skhoínos (rush or reed) and práson—leek (Jaeger 1944). Its English name, chives, derives from the Latin word for onion (cepa).
Chives do not produce large bulbs, but instead send out new axillary shoots after 2 or 3 leaves have formed, with shoots attached to short rhizomes (Brewster 1994, Hilty 2011). The plant forms dense clumps with narrow, linear, hollow leaves, typically 15–30 cm tall. The flowers are packed in dense umbels and do not produce bulbils (small bulbs), in contrast to many other Allium species, which have more space between flowers and often produce bulbils.
Chive leaves and flowers are both edible. The leaves are widely used as a culinary herb in the cuisines of Europe; the flowers are used in salads. The flavor is similar to but milder than other onions. Chives can be used fresh or dried.
Chives produce sulfur compounds (including methyl sulfides and disulfides) similar to those found in garlic, but in much smaller amounts. They are considered to have similar medicinal properties (antifungal, antimicrobial, improving circulation, etc.), but they have limited use for medicinal purposes. The sulfur compounds appear to be produced in large enough quantities, however, to help ward off insect pests in gardens, so chives are used in companion planting.
Chives have been in cultivation in Europe at least since the 16th century; records of related Alliums, including onions, garlics, and leeks, are found in Egyptian and Mesopotamian records dating to 5000 B.C. The Romans believed chives could relieve the pain from sunburn or a sore throat, and that eating chives would increase blood pressure and acted as a diuretic (Wikipedia 2011).
Chives are primarily grown in home gardens and small farms. The total area commercially harvested globally in 1990 was 1000 hectares, with Denmark, New Zealand, and Germany leading production (Brewster 1994).
In North America, the native species is variously classified as A. sibiricum, A. schoenoprasum var. sibiricum, or A. schoenoprasum var. laurentianum, but cultivated varieties have escaped and naturalized and are interfertile with native ecotypes, so that distinguishing native from introduced types and mapping the native range and assessing its invasiveness is difficult (FNA 2011, Michigan Flora Online 2011). It appears that chives primarily invade disturbed areas adjacent to cultivation; the species is not as invasive as A. vineale, crow garlic, or A. canadense, wild garlic (Hilty 2011).