How to Grow Cornflower
Cornflower At a Glance
Difficulty
Easy
Category
Flower
Sun Exposure
Full Sun
Frost Tolerance
Frost Hardy
Cold Hardiness
Survives to -12°C
Plant Family
Asteraceae
Growing Season
Cool Season
Plant Lifecycle
Annual
How to Start It
★ Recommended for beginners
Cornflowers shrug off frost, so sow them about 2 weeks before your last spring frost, right where they will flower, since they dislike being moved. Sow the seeds 1 cm deep, a few every 20 cm, and cover them. They sprout in 7 to 14 days: keep the strongest seedling at each spot. In milder areas, a fall sowing gives bigger plants that flower earlier the next year.
Cornflower, also called bachelor's button, is one of the easiest flowers you can grow, famous for its true-blue blooms that bees and butterflies love. It grows fast, is happy in poor soil and often seeds itself, so a patch can come back for years. The petals are edible and keep their colour when dried.
When To Start
Cornflower likes cool weather. Sow it in early spring, as soon as the ground can be worked.
We do not have exact sowing dates for this one yet.
When should you plant Cornflower?
Your planting dates depend on your local climate. Sign up and add your location to unlock personalized dates.
Your Cornflower Planting Window
Start planting
May 15, 2026
Last chance
Sep 10, 2026
Your Cornflower Calendar
Set your location to turn these into exact dates and reminders.
Sow cornflowers outdoors now, where they will flower
2 weeks before your last frost· every year
Cut cornflowers and pick off faded ones to keep them blooming
60 days after your last frost· every year· optional
Did you water your cornflower seedlings today? Keep the top of the soil damp until they are up and growing.
About 1 days after you plant it
Hello from your cornflowers! Thin crowded seedlings so each plant has room to grow.
About 30 days after you plant it
Cornflower check! Cut faded flowers often to keep new blooms coming.
About 90 days after you plant it
The Journey Ahead
Cornflower's Lifecycle
Seedling
Mature Plant
Seed Production
Step 2
Planting & Sprouting
Expect sprouts in 7–14 days
Growing Tips
- 1Plant cornflowers in full sun, at least 6 hours a day.
- 2Plain, well-drained soil is best, with only a little compost, since rich soil gives floppy, leafy plants.
- 3Water seedlings until they are growing well, then only in long dry spells.
- 4Skip extra feeding, as cornflowers flower best on lean soil.
- 5Push a few twiggy sticks around tall types, or grow them close together, so they hold each other up.
- 6If aphids cluster on the stems, wash them off with a spray of water, and space the plants so air flows and keeps mildew away.
Seedling Phase
Step 3
Growth & Maturity
80 cm
Mature Height
25 cm
Mature Width
Pests to Watch For
Diseases to Watch For
Mature Plant
Step 4
Harvesting
When to Pick
Blooms late spring to summer; deadhead or cut to keep it going
How to Harvest
- 1Cut stems for the vase in the morning, when the flowers are just opening.
- 2Pick or snip off faded flowers every few days, because a plant left to make seed soon stops blooming.
- 3Sprinkle the petals on salads or cakes for a pop of blue.
- 4Hang small bunches upside down in a dark, airy spot to dry them for crafts or tea blends.
- 5Pull the plants once they look tired in late summer, leaving a few heads to drop seed if you want them back next year.
Step 5
Saving Seeds
How to Save Seeds
Cornflower seeds come true if the variety is not a hybrid (hybrid F1 seeds will not), but bees can cross different colours, so a mixed patch gives mixed colours. Leave a few flower heads on the plant until they turn brown and dry, and pick them before they open and scatter. Rub the heads over a bowl to free the slim seeds, which have a little tuft of bristles at one end. Let them dry a few more days. Store them labelled in a cool, dark, dry place, where they keep a few years.
Seed Production
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