Welsh onion
Allium fistulosum
In a typical UK garden, sow indoors early February to late March, sow outside late March to late June, plant out late March to mid-June, and harvest early March to late November.
When to sow, plant and harvest
Last frost around 20 April, first frost around 31 October.
- Sow indoors
- early February to late March
- Sow outdoors
- late March to late Junelate August to mid-September
- Plant out
- late March to mid-June
- Harvest
- early March to late November
Growing facts
- Spacing
- 20 cm apart, rows 30 cm apart
- Square foot
- 4 per square (30 cm squares)
- Sowing depth
- 1 cm
- Ready in
- 60 to 90 days from sowing
- Grows to
- 50 cm
- Hardiness
- Hardy to about -15 °C
- Sun
- Full sun
- Crops for
- Several years (perennial)
Growing tip
Pull or cut a few stems at a time and the clump keeps multiplying; earth up stems for longer white shanks.
Neighbours
Alliums are one crop rotation group. Try not to grow them where any of the family grew in the last two or three years. How crop rotation works
More alliums
Where these figures come from
Every crop in VegLog was checked against published growing advice. Dates are worked out from average frost dates, so they shift with your garden. For welsh onion, we used:
Grow welsh onion with VegLog
Add welsh onion to a bed and VegLog reminds you when to sow, plant out and pick, timed to your own town's frost dates.
