A cornflower is a wildflower with brilliant blue petals that once grew commonly in European grain fields, especially among wheat and barley.

Cornflowers bloom with a distinctive bright blue color that's so recognizable it's often called cornflower blue. The petals have ragged, frilly edges that make each bloom look a bit like a tiny blue explosion. While farmers once considered cornflowers weeds because they competed with grain crops, many people loved their cheerful color dotting golden fields. Today, gardeners deliberately plant cornflowers because they're beautiful, easy to grow, and excellent at attracting butterflies and bees.

The flower appears frequently in art and poetry, and cornflower blue describes a particular shade of bright, pure blue. Vincent van Gogh painted cornflowers, and the color appears in everything from crayons to fashion. Modern farmers' use of herbicides has made wild cornflowers much rarer in European fields, but they remain popular garden flowers around the world.