Often seen growing as a weed in fields and along roads and railroads, Cornflower is a hardy, low maintenance cool season annual with striking blue flowers in the Asteraceae (aster) family. Genus came from the popular name of various plants in the late 14th century, from Medieval Latin centaurea, from Latin centaureum, from Greek kentaureion, from kentauros "centaur", so called because the plant's medicinal properties were discovered by Chiron the centaur. Specific epithet means blue for flower color. Plants reseed and naturalize easily so dead-heading is necessary to control the seeds. However, if the goal is to bring birds and butterflies into the garden, limit the dead-heading. It is an attractive and long-lasting cut flower. Because it does better in cooler climates, seeds should be started indoors 6-8 weeks before last frost, or in mild winter climates can be seeded in situ directly outdoors in the fall. Cornflower is very adaptable and will tolerate poor soils and no fertilization. It tolerates low water conditions but prefers medium moisture, well-drained soils. Cornflower prefers full sun to light shade but the stems will flop with too much shade. Taller plants may need staking or need to be planted with other plants that will hold them up. A blue cornflower was featured by Corning Glass Works in their initial oven-to-table ware line. It became the trademark of Corning consumer products for three decades. Place the plant in a container to better control the seeds or a naturalized area where the plant will reseed itself. Insects, Diseases, and Other Plant Problems: They have no serious insect or disease problems to note. Wilt, rots and rusts are possible. Also watch for aphids and mealybugs.
Curated pairwise relationships between this plant and others in the library — who feeds
whom, who competes, who confuses the pests. Green reads as a good pairing, red as one to avoid.
No curated interactions recorded for this species yet.
Also noted by NC State
Related species the NC State Plant Toolbox flags for this plant — look-alikes to tell
apart, and plants that play a similar role in a planting. Ones we carry in the library are linked.
Full sun (6 or more hours of direct sunlight a day) | Partial Shade (Direct sunlight only part of the day, 2-6 hours)
Soil texture
Clay; High Organic Matter; Loam (Silt)
Soil pH
Acid (<6.0); Alkaline (>8.0); Neutral (6.0-8.0)
Soil drainage
Good Drainage | Moist
Available space
Less than 12 inches
Mature size
Height: 1 ft. 0 in. - 3 ft. 0 in. | Width: 1 ft. 0 in. - 2 ft. 0 in.
Growth rate
Medium
Maintenance
High
Canopy layer
4 - Herbaceous (3-15 ft)
Form & Appearance
Habit / form
Erect
Texture
Medium
Leaf color
Gray/Silver; Green
Leaf type
Simple
Leaf arrangement
Alternate
Leaf shape
Lanceolate; Pinnatifid
Leaf margin
Lobed
Leaf feel
Smooth
Leaf size
1-3 inches long, < 1 inch wide
Hairs present
Yes
Leaf detail
Leaves are alternate, 1 to 4 inches long, pointed at the tip that are sparsely to moderately covered in long, matted hairs, a distinguishing characteristic of this plant.
Flower color
Blue; Pink; White
Flower value
Edible; Good Cut; Showy
Flower form
Cyme; Head
Flower shape
Wheel
Flower size
1-3 inches
Flower detail
An intense blue color arranged in heads approximately 1.5 inches in diameter, with a ring of a few large, spreading ray florets surrounding a central cluster of disc florets
Bloom time
Summer
Fruit color
Cream/Tan
Fruit type
Achene
Fruit size
< 1 inch long, < 1 inch wide
Fruit detail
Finely hairy, straw-colored at maturity with a tuft of short, stiff, light brown bristles at the tip.
Stem color
Gray/Silver; Green
Stem detail
Single stems from the base of the plant that then branch, are sparsely to moderately covered in woolly hairs; initially erect but tend to flop over without support of surrounding vegetation or stakes.
Wildlife & Ecology
Native status
Non-native
Origin
Western Asia, Europe
Distribution
Throughout the US and southern Canada
Wildlife value
Birds and butterflies use the flowers and fruit as a food source