Also sometimes written as "bachelor's buttons," they were sometimes "placed in the buttonhole of a suit or shirt; decades ago, bachelors sported the flower when they went courting," according to Colorado State Extension.
These flowers are prized as one of the true-blue wildflowers. The common name can refer both to the annual known to botanists as Centaurea cyanus (seen in the image above) and to perennial bachelor buttons, Centaurea montana.
