The confusion between the terms “cornflower” and “bachelor button” is common among gardeners. These names often appear interchangeably on seed packets and plant tags, leading many to wonder if they refer to two distinct species. The answer is that they are the same plant, but the variation in local and historical naming conventions causes the confusion. This situation highlights the inconsistencies that arise when relying solely on common names for plant identification.
Clarifying the Relationship Between the Names
Botanically, the names cornflower and bachelor button are synonyms for the same annual plant species: Centaurea cyanus. This plant is a member of the daisy family, Asteraceae. The definitive identification rests on the scientific name, which is unique and avoids the ambiguity of popular usage.
The difference between the two names is purely a matter of regional preference and historical context rather than any biological distinction. In Europe, “cornflower” is more prevalent due to its traditional habitat. Conversely, “bachelor button” became popular in North America and other regions, often linked to its cultural use. This dual naming convention has persisted even as the plant has been cultivated globally.
The single scientific binomial, Centaurea cyanus, provides the clarity that common names lack, confirming that both names describe the same plant. While other perennial plants in the Centaurea genus exist, the annual species is the one most commonly associated with both the cornflower and bachelor button monikers.
Identifying Features of Centaurea cyanus
The plant is an annual species, typically growing one to three feet tall. Its stems are slender, branching, and possess a slight gray-green coloration, often covered in fine, woolly hairs. This textured appearance is also visible on the leaves, which are long, narrow, and lance-shaped, usually measuring between one and four inches in length.
The flowers of Centaurea cyanus are distinctive, appearing as solitary heads on the ends of the stems. Each flower head, or capitulum, is composed of two types of florets: a central cluster of fertile disk florets surrounded by a ring of larger, sterile ray florets. These ray florets are deeply lobed and give the flower its characteristic fringed or ragged appearance.
The characteristic color of the wild species is an intense, vibrant blue, so much so that “cornflower blue” is a recognized color shade. The blue pigment responsible for this color is protocyanin. Cultivated varieties, however, have been bred to display a wide spectrum of colors, including shades of pink, white, deep maroon, and purple. The flower heads are relatively small, often measuring about one to one and a half inches in diameter.
Why Two Names Persist: History and Modern Varieties
The name “cornflower” originated in Europe, where the plant was historically common as a weed growing among grain crops. In this context, “corn” was the general English term for cereal grains like wheat, rye, or barley. The plant thrived alongside these crops in open, sunny fields, which cemented the name in the European lexicon.
The alternative name, “bachelor button,” arose from a cultural practice popular among young men, particularly during the 19th century. Single men would wear a freshly picked flower in the buttonhole of their jacket lapel, known as a boutonnière. This practice was a way for a bachelor to signal his availability or romantic intent. The small, neat, button-like shape of the flower head lent itself perfectly to this fashion, thus establishing the enduring common name.
The continued use of both names is partly fueled by the diverse range of modern cultivars developed by breeders. These cultivated varieties feature traits like double flowers, dwarf growth habits, and non-blue colors, which can make them look significantly different from the wild blue form. Gardeners may sometimes apply one name to the classic blue variety and the other name to a new pink or white cultivar, mistakenly believing they are different species, which perpetuates the separate naming convention for the same Centaurea cyanus.