Tulips are bulb plants belonging to the Liliaceae family. About 120 species and as many as 15.000 varieties belong to this kind. Tulips naturally occur in southern Europe, northern Africa and southern Asia. They are also considered to be decorative plants, which are most frequently grown in the world. The real "tulip madness" spread across Europe, especially in the Netherlands, in 17th century, when some of the bulbs of this plant cost as much as tenement houses in the centre of Amsterdam (tulips' purchasing led many merchants to bankruptcy). Tulips have been recognized as one of the symbols of the Netherlands to this day.
