Spring Onions in Cambridge

Allium cepa

Spring Onion
Spring Onion · Allium cepa

Spring onions are fast-growing, mild-flavoured onions grown for their green stems and small bulbs. They are easy to grow and can be sown in succession for a continuous harvest. Hardy varieties can even be sown in late autumn to overwinter for an early spring crop. Spring onions don't take much space and grow well in containers or between slower-growing vegetables.

30 cm · Full Sun · Moderate Water

Add to garden

Calibrated to Cambridge · last frost ≈ 7 May

Sow outdoors August to October, harvest March to May. Frost risk October to May.
ActivityJanuaryFebruaryMarchAprilMayJuneJulyAugustSeptemberOctoberNovemberDecember
Sow outdoorsNoNoNoNoNoNoNoYesYesYesNoNo
HarvestNoNoYesYesYesNoNoNoNoNoNoNo

Growing guide

Step-by-step instructions for growing Spring Onion

Growing guide for

Change the guide to see different planting timelines and tips.

Guide for sowing spring onions in autumn to overwinter for an early spring harvest.

  1. 01

    Sow Seeds in Autumn

    25 Aug to 1 Oct

    August to October is a good time to sow a winter-hardy spring onion variety (e.g. 'White Lisbon') for overwintering. Sow seeds about deep in an open, sunny spot. If autumn weather is dry, keep the seed bed moist to encourage germination before winter sets in.

  2. 02

    Winter Care

    19 Oct to 26 Feb

    As temperatures drop, ensure the bed is weed-free and protect seedlings in extreme cold. If hard frosts or snow are expected, cover the young plants with fleece or a cloche. Good drainage is important over winter to prevent the onions rotting in waterlogged soil.

  3. 03

    Thin in Spring

    3 Mar to 7 May

    When growth resumes in early spring, thin the overwintered seedlings to apart if they are crowded. Thinning in spring will give the remaining onions space to swell before harvest.

  4. 04

    Harvest

    16 Mar to 10 May

    Overwintered spring onions will be ready to harvest in spring, earlier than spring-sown crops. Pull them up from about March to May once they reach a good size. Enjoy them fresh, as their flavour is best straight from the garden.

Companion plants

Tap a plant to see why it works (or doesn't) with Spring 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.

Spring Onion guides by town

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