What Is the Difference Between a Cornflower & a Bachelor's Button?

Name

• Bachelor’s buttons and cornflowers refer to the same group of species within the genus Centaurea. This group is also commonly referred to as basket flowers, blue-bottles or bluets. Because they make such long-lasting cut flowers, they used to be used as adornments in suits or shirts. The name “bachelor’s buttons,” in fact, comes from the fact that bachelors used to put them in their buttonholes when visiting ladies.

Hardiness

• Cornflowers or bachelor’s buttons comprise many species, some of them perennial and some annual. The annual cornflower (Centaurea cyanus), for example, is a true annual in that it grows, blooms and sets seed within a single growing cycle, but self-sows so readily that it can be effectively considered a perennial in U.S. Department of Agriculture plant hardiness zones 2 thorugh 11. Perennial cornflower (Centaurea montana), also called mountain bluet, on the other hand, is a true perennial hardy to USDA zones 3 through 8. Pink bachelor’s button (Centaurea pulcherrima) is also a perennial, hardy to USDA zones 4 through 8.

Appearance

• Cornflowers typically have smallish, radial blooms 1 1/2 to 2 inches in diameter and look a little like thistles. They typically grow to heights between 1 and 3 feet, though dwarf varieties may be even shorter. They branch naturally and bloom profusely, but you can encourage branching and increased blooming by pinching off shoots. Cornflowers come in colors ranging from pink to white to blue and purple, and often have centers of a different hue than petals.

Culture & Uses

• Plants are usually quite tolerant, often putting up with drought as well as dry or rocky soil conditions. Do not water them too frequently as stems tend to get floppy when they are overwatered. Cornflowers like to be divided every two years or so. Their bright blooms put them at home in beds, borders, wildflower meadows or informal gardens. Flowers are often attractive to birds or butterflies. They also make excellent, long-lasting cut flowers for bouquets and arrangements.