How to grow Onion Sets (Sturon)

Allium cepa

🥕 Vegetable 🌱 Grown each year

Reliable, round, golden onions from sets — far easier than seed, and they store well into spring.

At a glance: Sow mid March to late April, harvest from mid July.

When to sow, plant and harvest

JanFebMarAprMayJunJulAugSepOctNovDec

Sow outdoors

Harvest

Timed for a typical UK garden (last frost mid-April). The app uses your own town's frost dates.

Mid March – late April · 4 weeks before the last spring frost
Plant Sets
Plant sets 10 cm, rows 30 cm apart apart in rows.
14–28 days after “Plant Sets” · Late March – mid April
Look for Shoots
Green shoots should be showing. Keep weeds down — these crops hate competition.
45–60 days after “Look for Shoots” · Mid May – late May
Remove Flower Spikes
Snap off any flower stems that appear — they ruin storage.
21–35 days after “Remove Flower Spikes” · Early June – mid June
Weed and Water
Hoe off weeds between rows and water in dry spells — even moisture gives better crops.
120–150 days after “Plant Sets” · Mid July – mid August
Harvest
When leaves yellow and flop over, lift on a dry day.
7–21 days after “Harvest” · Late July – early August
Dry and Store
Dry in the sun or a shed for 2 weeks until skins rustle, then store in nets somewhere cool.