Scilloideae is a large subfamily of the monocot family Asparagaceae in the order Asparagales, in itself the largest grouping within the monocots. The Scilloideae are herbaceous perennial bulbous flowering plants, which have sometimes been placed in a separate family, the Hyacinthaceae.
Scilloideae are distributed predominantly in Mediterranean climates including South Africa, Central Asia and South America. They have six tepals and six stamens with a superior ovary, which placed them previously within the lillies. They are characterized by their fleshy mucilaginous leaves arranged in a basal rosette and by the possession of poisonous substances ( bufodienolides and cardenolides).
The subfamily was recognized by modern classification systems such as the APG classification system III (2009) and APWeb (2001 onwards). The subfamily was already recognized by the earlier APG II but it left as an option the exclusion of the Hyacinthaceae.
Some genera are very popular as garden plants, such as hyacinths, grape hyacinths, squill and bluebell, and are important as cultivated plants and cut flowers.