How to Grow Welsh Onion
Allium fistulosum
Hardy Cool Season Continuous Harvest
Welsh onion is a hardy bunching onion that regrows after cutting and multiplies by division. Sow direct or transplant in spring or autumn. Harvest the hollow green leaves and white stems throughout the year. Split clumps every couple of years to keep them vigorous.
When to Start
Direct sow outdoors as soon as soil reaches 5°C — typically early to mid spring. Can also be started indoors 3 weeks earlier for a head start.
Don't know your frost date? Find it here →
Growth Stages
Sow seeds
Day 0 Germination
~10 days Harvest
~70 days Seed to harvest ~70 days
Approximate days from start
Care Essentials
- Light balanced feed at planting. Established plants rarely need feeding. Avoid excess nitrogen which produces soft, disease-prone growth.
- Hardy perennial treated as annual or biennial. Clumps multiply year on year. Edible green tops and white stems. Milder than onion, stronger than chives.
Growing Conditions
- Min. soil temperature
- 5°C+
- Germination temperature
- 10–25°C
Pet Safety
Don't know your frost date? Find it here
- Sow indoors
- —
- Transplant out
- —
- First harvest
- —
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Spacing & Planting
| Plant spacing | 10 cm |
| Row spacing | 30 cm |
| Sow depth | 1 cm |
| Mature height | 60 cm |
| Mature spread | 15 cm |
Growing Conditions
| Min. soil temperature | 5°C |
| Germination temperature | 10–25°C |
| Base growth temperature | 5°C |
| Min. daylength to start | 8h |
| Photoperiod sensitivity | day neutral |
Frequently Asked Questions
- How far apart should I plant Welsh Onion?
- Plant Welsh Onion 10cm apart with 30cm between rows.
- When can I harvest Welsh Onion?
- Welsh Onion is ready to harvest approximately 50 days after transplanting.
- Is Welsh Onion frost hardy?
- Welsh Onion is classified as Hardy.
