The cornflower (Centaurea cyanus) is a classic flowering plant also known as bachelor’s button or bluebottle. This annual wildflower is native to Europe, where it historically grew among grain crops. The name “cornflower” refers to its traditional association with these grain fields. It has since been introduced and naturalized across many other parts of the world, including North America, often through its use as an ornamental garden plant.
Identifying Features of the Flower
The most striking characteristic of the cornflower is its bloom, which typically measures about 1 to 1.5 inches across. While the classic variety is known for its intense, vivid blue color, cultivated forms also appear in shades of pink, white, and purple. The flower is a composite head, meaning it is made up of many small flowers clustered together, similar to a daisy.
The outer ring consists of large, spreading ray florets that look like petals. These ray florets are deeply lobed or fringed, giving the entire bloom a distinct, ragged appearance. The center of the flower head is packed with a cluster of smaller, fertile disk florets.
Characteristics of the Stem and Leaves
The cornflower plant generally grows to a height of 1 to 3 feet, though it can range from 8 to 39 inches tall. It features slender, branched stems that often have a slightly weak structure. The stems are sparsely to moderately covered in fine, woolly hairs, giving them a textured feel.
The foliage is long and narrow, typically described as lance-shaped or linear, ranging from 1 to 4 inches in length. The leaves are pointed at the tip and are often a grayish-green color. This color comes from a sparse covering of matted hairs on their surface, providing a subtle contrast to the bright flowers.
Typical Habitat and Growth Patterns
Cornflowers are historically associated with open, disturbed ground, having been a common weed in fields of wheat, barley, and other grains. They are native to temperate Europe but have become naturalized globally, often found along roadsides, in waste grounds, and in meadows. The plant prefers full sun and well-drained soil, showing good tolerance for poor soil conditions and low-water situations once established.
The cornflower is an annual, completing its growth, flowering, and seeding process within a single season. It is a cool-weather annual that thrives in cooler spring weather and may fade quickly once the intense heat of summer arrives. The plant will readily self-seed in gardens if the spent flowers are not removed.