Original "Tulipa" species can be obtained for ornamental purposes, such as "Tulipa tarda" and "Tulipa turkestanica". These are referred to as species, or botanical, tulips, and tend to be smaller plants but better at naturalising than the cultivated forms. Breeding programs have produced a wide range of tulip types, enabling blooming through a much longer season by creating early, mid- and late spring varieties. Fourteen distinct types are available in addition to botanical tulips, including Lily-flowered, Fringed, Viridiflora and Rembrandt. In addition to blooming season, tulip varieties differ in shape, and height, and exhibit a wide range of colours, both pure and in combination.