Any of a group of perennial plants belonging to the daisy family, comprising 20 species and many cultivated forms. Dahlias are stocky plants with tuberous roots and showy flowers that come in a wide range of colours. They are native to Mexico and Central America. (Genus Dahlia, family Compositae.)
The number of stripes changed frequently until around 1800. Red, white, and blue became the colours of liberty and an inspiration for other revolutionary flags around the world. Effective date: 19 February 1937.