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Tall Blue cornflowers with long stems and vivid blue blooms in a garden

How to Grow Cornflower Tall Blue From Seed

By Maxim Kaufman — Founder & CEO, Organo Republic

Updated July 2026

Cornflower Tall Blue is the true-blue classic, the bachelor's button gardeners have loved for generations. Its plants stand a stately 30 to 36 inches tall, sending up long, wiry stems topped with those famous vivid blue, fringed blooms. That height makes it one of the very best cornflowers for cutting, giving you armloads of long-stemmed flowers for fresh and dried bouquets. Like all cornflowers it is a tough, easy hardy annual that thrives in full sun and lean soil.

This is the quick guide to Cornflower Tall Blue. For the full step-by-step on sowing, spacing, feeding, deadheading, and troubleshooting cornflower, see our complete guide to growing cornflower from seed.

Quick start

Direct sow Tall Blue in early spring as soon as the soil can be worked, or in fall in mild-winter areas, since it dislikes transplanting. Cover the seed about a quarter to half an inch deep (it needs darkness to sprout) and keep it evenly moist until it germinates in one to two weeks. Thin seedlings to stand 9 to 12 inches apart and stake or grow through a grid, because these tall stems can flop in wind. Expect blooms in about 65 to 90 days, and cut or deadhead often to keep them coming.

Best tip

Support these tall stems early and cut generously. At 30 to 36 inches, Tall Blue can lean or flop in wind or rich soil, so set twiggy stakes or a grow-through grid while plants are young rather than trying to prop them up later. Then cut freely: the more long-stemmed blooms you harvest, the more the plant produces. A climate note: sow early because Tall Blue puts on its best show in cool spring weather and slows once real summer heat arrives, so an early or fall sowing gives the strongest, tallest plants.

At a glance

How to Grow Cornflower Tall Blue From Seed — growing specifications at a glance
Botanical name	Centaurea cyanus
Plant type	Annual flower
USDA zones	2 to 11 (grown as an annual)
Sun	Full sun
Days to maturity	65 to 90 days to bloom
Height	30 to 36 in
Spacing	9 to 12 in
Water	Low to moderate; drought-tolerant once established

Uses

Tall Blue is first and foremost a cut-flower cornflower. The long, strong stems and intense blue blooms make gorgeous fresh bouquets and hold their color beautifully when dried for everlasting arrangements and crafts. In the garden the tall plants add height and that unmistakable blue to cottage borders and meadow plantings, while the nectar-rich flowers pull in bees, butterflies, and beneficial insects. The petals are edible too, perfect for scattering over salads and cakes or drying for tea blends.

Frequently asked questions

How tall does Cornflower Tall Blue get?

Tall Blue is a taller cornflower, reaching about 30 to 36 inches. Those long stems are exactly what make it such a good cut flower, though they may need light staking in windy or exposed spots.

What color are Tall Blue cornflowers?

Tall Blue is the classic, vivid true-blue bachelor's button, with fringed, thistle-like blooms in that deep cornflower blue gardeners prize for bouquets and dried arrangements.

Is Tall Blue cornflower good for cut flowers?

Yes, it is one of the best. The long, strong stems and intense blue color make excellent fresh bouquets, and the blooms dry beautifully for everlasting arrangements. Cut in the cool morning as buds just open for the longest vase life.

When will Tall Blue cornflower bloom?

From an early spring or fall sowing, expect flowers in roughly 65 to 90 days, generally from late spring into summer. Regular cutting and deadheading keeps new blooms coming for weeks.

Ready to grow your own true-blue cornflowers? Start with our non-GMO, heirloom wildflower seeds for armloads of long-stemmed blue blooms, and explore the whole wildflower seed collection to build your cutting garden.

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Wildflower Seed Mix – Non-GMO HeirloomBest value21 annual wildflowers in one packet, including cornflower, for a fast, colorful, pollinator-friendly meadow.

Price$24.99 Sale Price$22.99

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Want more easy color? These non-GMO wildflower mixes pair beautifully with Tall Blue cornflower:

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Perennial Wildflower Seeds Mix – Non-GMO HeirloomComes back yearly16 perennial wildflowers that return year after year, pairing perfectly with self-seeding cornflower.

Price$14.99Starting at$12.99

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Butterfly Garden Wildflower Seeds Mix – Non-GMO HeirloomPollinator magnet23 wildflowers chosen to feed birds and butterflies, a natural companion to bee-loving cornflower.

Price$14.99Starting at$12.99

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By Maxim Kaufman — Founder & CEO, Organo Republic

Maxim founded Organo Republic in 2017 and personally selects, tests, and grows the heirloom, non-GMO varieties the company offers. Under his leadership, Organo Republic was named Agri Business Review’s Top Non-GMO Seed Variety Solution 2026.