The question of whether Cornflower and Bachelor's Button refer to the same plant is an excellent example of the challenges posed by common plant names. From a botanical perspective, the answer is a definitive yes. Both names are used to describe the same species, Centaurea cyanus. The confusion arises because common names are regionally and culturally specific, unlike the universal scientific name governed by the International Code of Nomenclature for algae, fungi, and plants (ICN). The name "Cornflower" is derived from the plant's historical prevalence as a weed in cornfields (where "corn" referred generically to grain crops in Europe). "Bachelor's Button" is thought to originate from the practice of young men (bachelors) wearing the flower in their buttonholes to signify their romantic availability or to ward off love's misfortunes.
Scientifically classified as Centaurea cyanus, this plant is a member of the Asteraceae family, one of the largest families of flowering plants. Key morphological characteristics confirm its identity regardless of the common name used. Centaurea cyanus is an annual herbaceous plant, typically growing 30 to 90 centimeters tall. Its leaves are lanceolate (lance-shaped) and arranged alternately on the stem, with the lower leaves often being slightly lobed. The most distinguishing feature is the flower head, which is not a single flower but a composite inflorescence. What appear to be petals are actually sterile, enlarged ray florets that surround a central cluster of tiny, fertile disc florets. The most iconic and wild-type color is a vivid, deep blue, a relatively rare color in the plant kingdom, though cultivated varieties now exist in pink, white, purple, and maroon.
Historically, Centaurea cyanus was a common sight in agricultural landscapes across Europe, thriving as a native species in the nitrogen-poor soils of grain fields. Its life cycle was synchronized with cereal crops like wheat and barley. However, with the intensification of agriculture and the widespread use of modern herbicides in the 20th century, its populations as a wild native have declined significantly in many areas. Today, it is often classified as a conservation concern in its native range. Conversely, the plant has been widely introduced and naturalized in other parts of the world, including North America and Australia. Its popularity as an ornamental garden plant, sold under both the "Cornflower" and "Bachelor's Button" names, has ensured its continued presence. It is valued for its vibrant color, ease of growth from seed, and attractiveness to pollinators like bees and butterflies.
The horticultural industry has developed numerous cultivars of Centaurea cyanus that are marketed under both common names. These include dwarf varieties suitable for containers, double-flowered forms with extra layers of ray florets, and the expanded color palette mentioned previously. It is important to distinguish Centaurea cyanus from other plants that may share similar common names. For instance, the name "Button" is applied to many flowers with button-like shapes, such as certain types of daisies. Furthermore, other species within the large Centaurea genus, which includes knapweeds and star-thistles, may be confused with the true Cornflower/Bachelor's Button. However, the unique combination of its annual habit, slender grey-green leaves, and distinctive blue composite flowers makes Centaurea cyanus readily identifiable to botanists and experienced gardeners.
