Onions in Barnacle
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
Prepare the Bed
1 Mar – 16 MarWork the soil from 1st March - 16th March, 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
1 Apr – 15 AprPlant sets from 1st April - 15th April, with the tips just showing above the soil. Space them apart in rows apart, then water in thoroughly straight away.
Keep Weed Free
8 Apr – 6 Augevery 3 weeksFrom 8th April to 6th August, 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
6 Aug – 5 SeptLift bulbs from 6th August - 5th September 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.
Related Plants
Explore similar plants you might like
Basil
Basil is a fragrant, tender herb whose leaves are a staple of summer cooking. Native to tropical regions, basil is treated as an annual in temperate climates like the UK because it cannot tolerate frost. It thrives in warm, sunny conditions and can be grown in garden beds or pots for a steady supply of fresh, flavourful leaves throughout the summer.
Brussels Sprouts
Brussels sprouts are a hardy winter brassica (cabbage family) that form sturdy, leafy stems often around 60–90cm tall. They produce edible mini-cabbage buds along the stem from autumn through winter. Thanks to their cold tolerance, sprouts remain productive into late winter, and frost actually improves their sweetness.
Calabrese
Calabrese (broccoli) produces a large central head of tightly-packed green buds, followed by smaller side-shoots after the main head is cut. It’s a cool-season brassica crop. Grow it in full sun with fertile, well-drained soil and keep plants watered during dry spells. Harvest the heads while firm, then leave the stem in the ground to allow side-shoots to develop.
Also in nearby towns
See how Onion timing shifts in other towns with different frost dates.