Some are annual flowers and some are perennial, but all are great additions to the gardener's palette. Centaurea also make excellent cut flowers for both fresh and dried arrangements. Also known as cornflower, the plants grow from 1-3 feet tall, depending on the cultivar. Though blue is the more classical color, cultivars are also available in red, pink, white and purple. Flowers appear in early-mid summer and will repeat their show in early autumn, if the plants are trimmed back immediately after summer bloom.
Flowers are most commonly blue, but there are cultivars with pink, white or purple blooms.
Mountain bluet is winter-hardy but will benefit from division every couple of years to maintain healthy, blooming plants. Persian cornflower, Centaurea dealbata , is a lovely pink-flowered perennial with flowers a little larger than C. montana . Annual cornflowers can be started indoors from seed about a month or so before your frost-free date, or you can directly sow the seed outdoors. Perennial Centaurea can be propagated either by seed or division, but division is recommended if you want to maintain a particular flower color or habit.