Onion
Allium cepa
A hardy allium for UK gardens, usually grown from sets for the easiest crop or from seed for more choice. It needs free-draining soil, steady weeding and a careful cure before storing.
Growing Guide
Step-by-step instructions for growing Onion
Planting Calendar
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Prepare the Bed
Work the soil from , making sure it drains freely and has a fine tilth. Mix in compost or well-rotted manure, but avoid fresh manure, which encourages soft growth and poorer bulbs.
Plant Sets
Plant sets from , with the tips just showing above the soil. Space them apart in rows apart, then water in thoroughly straight away.
Keep Weed Free
every 3 weeksFrom to , hoe between rows lightly and hand weed close to the bulbs so they do not get crowded out. Water during dry spells while the bulbs are swelling, and keep the soil evenly moist rather than soggy.
Lift and Cure Bulbs
Lift bulbs from when the tops yellow and fall over. Dry them in a warm, airy place for before storing, then trim off roots and loose tops once they are fully cured.
Companion Plants
Tap a plant to see why it works (or doesn't) with Onion.
Good companions
Plants to avoid
Why companion planting matters
Companion planting can deter pests, improve pollination, and make better use of space. Some plants confuse pests or attract beneficial insects; others improve soil or offer shade to neighbours that need it.
Suggested Varieties
Popular varieties of Onion to consider
Sturon
A dependable maincrop onion with good storage qualities and firm, globe-shaped bulbs.
Red Baron
A reliable red onion with good colour and a steady crop from sets or transplants.
Senshyu Yellow
A well-known overwintering onion that can be planted in autumn for an early summer harvest in mild UK gardens.
Centurion
A widely grown, high-yielding set onion with good tolerance to bolting.
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