Onions in Ivy Todd

Allium cepa

Onion
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.

45 cm · Full Sun · Moderate Water

Add to garden

Calibrated to Ivy Todd · last frost ≈ 9 May

Plant out April, harvest September. Frost risk October to May.
ActivityJanuaryFebruaryMarchAprilMayJuneJulyAugustSeptemberOctoberNovemberDecember
Plant outNoNoNoYesNoNoNoNoNoNoNoNo
HarvestNoNoNoNoNoNoNoNoYesNoNoNo

Growing guide

Step-by-step instructions for growing Onion

  1. 01

    Prepare the Bed

    25 Mar to 9 Apr

    Work the soil from 25th March - 9th April, 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.

  2. 02

    Plant Sets

    4 Apr to 25 Apr

    Plant sets from 4th April - 25th April, with the tips just showing above the soil. Space them apart in rows apart, then water in thoroughly straight away.

  3. 03

    Keep Weed Free

    14 Apr to 12 Aug every 3 weeks

    From 14th April to 12th 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.

  4. 04

    Lift and Cure Bulbs

    1 Sept to 29 Sept

    Lift bulbs from 1st September - 29th 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.

Onion guides by town

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