When to plant Onions in Bristol

Allium cepa

Onion
Onion · Allium cepa

A hardy allium for UK gardens, grown from sets. Plant spring sets for a summer crop, or named overwintering sets in autumn for an earlier lift. It needs free-draining soil, steady weeding, and a careful cure before storing.

45 cm · Full Sun · Moderate Water

Add to garden

Calibrated to Bristol · last frost ≈ 19 Apr

Plant out March to April, harvest August to September. Frost risk November to April.
ActivityJanuaryFebruaryMarchAprilMayJuneJulyAugustSeptemberOctoberNovemberDecember
Plant outNoNoYesYesNoNoNoNoNoNoNoNo
HarvestNoNoNoNoNoNoNoYesYesNoNoNo

Growing guide

What to do through the growing season

Growing guide for

Change the guide to see different planting timelines and tips.

Plant spring sets for the simplest summer crop. This suits a sunny, free-draining bed.

  1. 01

    Prepare the Bed

    5 Mar to 20 Mar

    Work the soil from 5th March - 20th March. It must drain freely and have a fine tilth. Mix in compost or well-rotted manure. Do not add fresh manure.

  2. 02

    Plant Sets

    15 Mar to 5 Apr

    Plant spring sets from 15th March - 5th April, tips just showing. Space apart, in rows apart. Water in well.

    • Birds lift sets. Cover with fleece or mesh until they root.

  3. 03

    Keep Weed Free

    15 Mar to 3 Aug Dates as each sowing reaches this stage

    From 15th March to 3rd August, keep weeds down. Hand-weed close to the bulbs. Water in dry spells while the bulbs are swelling. Keep the soil moist, not soggy.

  4. 04

    Lift and Cure Bulbs

    2 Aug to 20 Sept Dates as each sowing reaches this stage

    Lift bulbs through 2nd August - 20th September, when the tops yellow and fall over. Dry them somewhere warm and airy for two to three weeks, then trim the roots and loose tops before storing.

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.

Onion guides by town

See how Onion timing shifts in other towns with different frost dates.