Cornflower is a cool-season annual that brings old-fashioned charm and vibrant color to any garden. Native to Europe, this hardy plant has naturalized across much of North America, thriving in hardiness zones 2 through 11. Delicate purple-blue flowers, sometimes pink or white, bloom prolifically from May through July on slender stems reaching 12 to 36 inches tall. It tolerates poor soils and drought with ease, making it one of the lowest-maintenance flowers you can grow. Plant cornflower in full sun, deadhead spent blooms to encourage more flowers, and you'll have a season-long display of blooms perfect for cutting or leaving to attract butterflies and birds.
9
Full Sun
Moderate
2-11
36in H x 24in W
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Moderate
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Cornflower flowers glow with an unmistakable deep blue-purple hue, each bloom reaching about 1.5 inches across and held on stems clad with distinctive narrow upper leaves. It thrives on neglect, tolerating poor soils, drought, and even some shade, though stems will stretch if light is limited. The real appeal lies in its dual nature: it's both a reliable garden workhorse for continuous color and a passable self-seeding volunteer that can naturalize in fields and along roadsides if you let it.
Cornflower is grown primarily as an ornamental annual, valued for its long season of showy blue flowers. It excels as a cut flower, bringing vibrant color to fresh arrangements. Many gardeners grow it specifically to naturalize in sunny borders and wild gardens, where it self-seeds reliably and attracts pollinators, creating a sustainable display year after year.
No timeline data available yet for this variety.
Sow seeds indoors 6 to 8 weeks before your last spring frost date. Transplant seedlings outdoors once soil can be worked and frost risk has passed.
Harden off seedlings gradually before moving them to the garden. Space plants 12 to 24 inches apart to allow for mature spread. Plant after the last spring frost date when soil is workable.
In mild winter climates, sow seed outdoors in fall. In most regions, direct sow at the last spring frost date. Press seeds into soil; they need light to germinate. Seeds will germinate in cool spring weather.
Cut flowers for arrangements when the blooms are fully open, typically in late May through July. Harvest in the morning after dew dries for longest vase life. Simply snip stems near the base and place immediately in water.
Deadhead spent flower heads regularly throughout the bloom season to prevent unwanted self-seeding and to extend flowering. If you wish to allow natural self-seeding, simply leave some flowers on the plant to mature and drop seed.
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“Centaurea cyanus has escaped from European gardens to become a familiar wildflower across the United States and southern Canada, typically appearing in fields, waste grounds, and along railroads and roadsides. This naturalization story speaks to the plant's resilience and its long history as a garden staple in temperate climates. Its journey from cultivated ornamental to naturalized wildflower reflects both its hardiness and its appeal to generations of gardeners seeking color without fuss.”