How to Grow Corn Cockle
Agrostemma githago
Hardy Cool Season
Corn cockle is a hardy annual wildflower for full sun and well-drained, poor to average soil. Sow seed directly where it is to flower — autumn sowing gives the strongest spring display; spring sowing flowers in summer. Thin seedlings to 15 cm apart and water during dry spells. No feeding needed. Deadhead to prolong flowering or leave a few heads to self-seed and naturalise. IMPORTANT — the seeds are toxic; keep away from children and pets.
In your Leaftide garden 
- Hardiness
- Hardy
- Season
- Cool Season
- Spacing
- 15 cm
- Height
- 90 cm
- Sow depth
- 0.5 cm
- Start from
- Seed
- Light
- Full sun
- Water
- Low
When to Start
Direct sow outdoors as soon as soil reaches 10°C — typically early to mid spring. Hardy enough to tolerate light frosts.
Don't know your frost date? Find it here →
Growth Stages
Sow seeds
Day 0 Germination
~14 days Flowering
~120 days Seed to harvest ~120 days
Approximate days from start
Care Essentials
- No feeding required — corn cockle thrives in poor to moderately fertile soil.
- Sow directly in autumn for the best spring display, or in early spring for summer flowers. Thin seedlings to 15 cm apart. Corn cockle self-seeds freely — allow a few plants to set seed to naturalise a wildflower patch. CAUTION — all parts of the plant, especially the seeds, are toxic if ingested.
Growing Conditions
- Germination temperature
- 5–18°C
Pet Safety
Cats: Toxic
Dogs: Toxic
Don't know your frost date? Find it here
Spacing & Planting
| Plant spacing | 15 cm |
| Row spacing | 20 cm |
| Sow depth | 0.5 cm |
| Mature height | 90 cm |
| Mature spread | 30 cm |
Growing Conditions
| Germination temperature | 5–18°C |
Frequently Asked Questions
- How far apart should I plant Corn Cockle?
- Plant Corn Cockle 15cm apart with 20cm between rows.
- Is Corn Cockle frost hardy?
- Corn Cockle is classified as Hardy.