The genus Muscari, commonly and collectively known as grape hyacinths, are a group of perennial plants native to Eurasia that produce spikes of dense, most commonly blue, urn-shaped flowers resembling bunches of grapes in the spring. White cultivars also exist.
The Muscari have originated in the old world, from the Mediterranean basin, the Center and South of Europe, Northern Africa, the West, Center and South-West of Asia. The term muscari comes from the Latin muscus, since the scent is said to resemble musk.
Classified as being in the family Hyacinthaceae, they have also been placed amongst the Liliaceae as a member of the Hyacintheae tribe. There are about forty species. These are subdivided into four groups, or subgenera; Botryanthus, Pseudomuscari, Leopoldia and Muscarimia. Leopoldia and Pseudomuscari have been considered by some authorities (e.g. Kew and Mobot) to have genus status. 
Sometimes considered to be the true Grape Hyacinths often called baby's-breath, the flowers are pale blue to blackish-blue, but albinos have been reported. The flower form is globose to obovoid with a constricted mouth. The flowers are in compact racemes which are dense, the flowers almost touching when first blooming and then becoming further spaced out. They are easy to cultivate, flowering in the spring. Species include M. armeniacum, M. argaei, M. aucheri, M. botryoides, M. commutatum, M. grandifolium, M. latifolium, M. neglectum. 
Pseudomuscari species flowers are shades of blue, pale or bright blue, and are small plants with dense racemes. Their characteristic feature is the bell-shaped perianth which is not constricted at the mouth. Includes M. azureum, M. chalusicum, M. macrocarpum, M. pallens (syn. Pseudomuscari pallens).
Leopoldia are generally taller plants than the first two groups, with more widely spread flowers on the raceme. The flowers are longer, often urn-shaped or tubular and have angular 'shoulders', just below the constricted mouth. The flower colour is a shade of white, yellow, green or brown but never blue. There may be a tuft of bright violet, blue or pink flowers at the top of the raceme which are sterile, the lower flowers being fertile. Leopolda blooms later in the season than Botryanthus and Pseudomuscari. Includes M. comosum.
Muscarimia group has two species. They have relatively large bulbs with thick fleshy perennial roots, and their natural habitat is Turkey and the east Aegean. The stems are stout and carry racemes with large elongated flowers with six projections below the mouth. The flowers are fragrant, yellow or white, tinted with green or blue, and small brown lobes. There may be a few sterile flowers which are minute and violet. They are best grown in a bulb frame or alpine house in a deep pot, since they have strong deep roots. Includes M. macrocarpum, M. massayanum (sometimes included in Leopoldia), M. muscarimi.
Some species are among the earliest to bloom in the spring. They are planted as bulbs and tend to multiply quickly (naturalise) when planted in good soils. They prefer well drained sandy soil, that is acid to neutral and not too rich. May be found in woodlands or meadows, they are commonly cultivated in lawns, borders, rock gardens and containers. They require little feeding or watering in the summer, and sun or light shade.
Species and cultivars
Muscari comosum bulbs are pickled and eaten in Iran under the name "موسیر" ([Moo'sir])and also in Greece under the name βολβοί ([vol'vi] lit. 'bulbs') and in the Basilicata and Puglia region of Italy, under the names "lampascioni", "lampasciuni", "lamponi". They are included in the Ark of Taste catalogue of heritage foods.
1. ^ Pacific Bulb Society: Muscari
* Horton A, McNair J. All About Bulbs. Ortho, San Ramon 1987
Source: Wikipedia, Wikispecies: All text is available under the terms of the GNU Free Documentation License