E-Flora BC: Electronic Atlas of the Flora of British Columbia

Centaurea cyanus L.
cornflower (bachelor's-button; garden cornflower)
Asteraceae (Aster family)

Introduction to Vascular Plants

© Stephanie Rivest  Email the photographer   (Photo ID #88495)

E-Flora BC Static Map
Distribution of Centaurea cyanus
Click here to view our interactive map and legend
Details about map content are available here
Click on the map dots to view record details.

Species Information

Click on the image below to view an expanded illustration for this species.

Annual herb from a taproot; stems erect, branched, loosely hairy, 0.2-1.2 m tall.
Basal leaves linear to lanceolate, entire or with a few teeth and narrow lobes towards the base, white-woolly below, up to 13 cm long and 1 cm wide, soon deciduous; stem leaves similar, reduced and narrower upwards.
Heads discoid, several to many, solitary at the ends of ascending branches; disk flowers usually blue, sometimes purple, pink or white, the sterile marginal ones about 18 mm long, enlarged apically with 5 lobes, the central ones perfect and about 15 mm long; involucres 20-25 mm tall, 12-15 mm wide; involucral bracts egg-shaped or lanceolate, grooved, with a darkened, tattered fringe at the tips, glabrous.
Achenes compressed, with appressed, soft hairs, 3.5-4 mm long; pappus of numerous, strongly graduated brown bristles.

Source: The Illustrated Flora of British Columbia

Habitat / Range

Dry roadsides in the lowland and montane zones; infrequent in S BC; introduced from the Mediterranean region.

Source: The Illustrated Flora of British Columbia


Ecological Framework for Centaurea cyanus

The table below shows the species-specific information calculated from
original data (BEC database) provided by the BC Ministry of Forests and Range.
(Updated August, 2013)

Site Information
Value / Class




Elevation (metres) 745 745 745
Slope Gradient (%) 52 52 52
Aspect (degrees)
[0 - N; 90 - E; 180 - S; 270 - W]
150 149 150
Soil Moisture Regime (SMR)
[0 - very xeric; 4 - mesic;
8 - hydric]
2 2 2
Modal Nutrient Regime
Number of field plots
 species was recorded in:
Modal BEC Zone Class
All BEC Zones (# of stations/zone) species was recorded in: ICH(1)


The climate type for this species, as reported in the: "British Columbia plant species codes and selected attributes. Version 6 Database" (Meidinger et al. 2008), is not evaluated, unknown or variable.

Synonyms and Alternate Names

Leucacantha cyanus (L.) Nieuwl. & Lunell

Taxonomic and Nomenclatural Links

Additional Photo Sources

General References