Blue Diadem Cornflower is a stunning heirloom variety of Centaurea cyanus that brings vibrant blue blooms to gardens from spring through summer. Standing a compact 30 inches tall, these flowers reach full bloom in just 70 days from seed, making them a rewarding choice for gardeners seeking quick color. The variety thrives in full sun with moderate water needs and tolerates drought once established, while its ability to attract pollinators and resist deer browsing makes it a functional addition to any landscape.
8
Full Sun
Moderate
2-11
30in H x 10in W
—
High
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Blue Diadem produces its signature deep blue flowers reliably within 70 days, flowering continuously from March through August in full sun. Once established, these plants handle drought with ease and need only an inch of water weekly initially, then water during dry spells. Deer avoid them entirely, and pollinators flock to the blooms, making this heirloom as ecologically generous as it is beautiful. The compact 30-inch height and 10-inch spread fit naturally into borders and cottage gardens without dominating the space.
Blue Diadem Cornflowers are grown primarily for their ornamental blooms, which appear in succession from spring through summer. The flowers work beautifully in cut arrangements and are valued by pollinators and wildlife gardeners for attracting beneficial insects.
No timeline data available yet for this variety.
Sow seeds directly outdoors in early spring, 3 to 4 weeks before your last frost date. In zones 7 through 10, you can also sow in October for fall germination. Barely cover seeds, pressing them lightly into the soil so light can reach them during germination.
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