How to Grow Flax
Linum usitatissimum
Flax is a fast-growing hardy annual producing a haze of sky-blue flowers over slender stems. Direct sow in spring or autumn in full sun and poor to average well-drained soil. Thin to 10 cm for good stem development. Flowers last only a morning but appear in continuous succession for weeks. Leave some seed pods to ripen for linseed harvest or self-seeding. An ancient dual-purpose crop equally at home as a meadow filler, cover crop, or cutting garden plant.
When to Start
Direct sow outdoors as soon as soil reaches 5°C — typically early to mid spring. Hardy enough to tolerate light frosts.
Don't know your frost date? Find it here →
Growth Stages
Approximate days from start
Care Essentials
- Rarely needed. Flax thrives in poor to average, well-drained soil. Feeding encourages leafy growth at the expense of flowers and fiber.
- One of humanity's oldest cultivated plants, grown for both fiber (linen) and oil (linseed). The sky-blue flowers last only a single morning but are produced in succession over several weeks. An excellent cool-season cover crop and cut-flower filler. Self-seeds freely if pods are left to ripen.
Growing Conditions
- Min. soil temperature
- 5°C+
- Germination temperature
- 10–18°C
Enter your last frost date to see your dates
- Direct sow
- —
- First harvest
- —
Want your full season plan with reminders? Try Leaftide free
Spacing & Planting
| Plant spacing | 10 cm |
| Row spacing | 15 cm |
| Sow depth | 1 cm |
| Mature height | 80 cm |
| Mature spread | 15 cm |
Direct sow and thin to final spacing. Dense sowings support slender stems and are traditional for fiber production. Wider spacing gives better branching and more flowers.
Growing Conditions
| Min. soil temperature | 5°C |
| Germination temperature | 10–18°C |
| Base growth temperature | 4°C |
| Photoperiod sensitivity | day neutral |
Frequently Asked Questions
- How far apart should I plant Flax?
- Plant Flax 10cm apart with 15cm between rows.
- When does Flax flower?
- Flax typically flowers approximately 100 days after transplanting.
- Is Flax frost hardy?
- Flax is classified as Hardy.
