gaillardia, any plant of the genus Gaillardia of the Asteaceae family (aster family), including annual, biennial, and perennial herbs with showy heads of red and/or yellow ray flowers and usually purple disk flowers. In the W United States they grow wild in large quantities (hence the name blanketflower); they are also popular garden flowers. Gaillardias are classified in the division Magnoliophyta, class Magnoliopsida, order Asterales, family Asteraceae.