Kohlrabis in Penisa'r Waun

Brassica oleracea var. gongylodes

Kohlrabi
Kohlrabi · Brassica oleracea var. gongylodes

A quick-growing brassica grown for its swollen stem, which tastes mild and crisp when picked young. It does best in cool UK conditions with steady moisture and protection from cabbage root fly and pigeons.

35 cm · Full Sun · Moderate Water

Calibrated to Penisa'r Waun · last frost ≈ 18 Apr

Sow February to July, harvest June to November. Frost risk November to April.
ActivityJanuaryFebruaryMarchAprilMayJuneJulyAugustSeptemberOctoberNovemberDecember
SowNoYesYesYesYesYesYesNoNoNoNoNo
HarvestNoNoNoNoNoYesYesYesYesYesYesNo

Growing guide

Step-by-step instructions for growing Kohlrabi

  1. 01

    Sow Seeds

    16 Feb to 19 Jul every 3 weeks

    Sow seeds around 16th February - 19th July in drills or short blocks, about deep. Sow a little at a time every 21 days for a steady run of crops rather than one large batch.

  2. 02

    Thin Seedlings

    13 May to 24 May

    From 13th May, thin seedlings so the strongest plants are left at apart. Keep the soil lightly moist so the remaining plants keep moving without checking.

  3. 03

    Protect From Pests

    18 Apr to 19 Jul

    From 18th April, cover the bed with fine mesh to keep out cabbage white butterflies and pigeons. Fit brassica collars snugly at the stem base to cut cabbage root fly damage, and check the netting after strong wind.

  4. 04

    Feed Plants

    2 May to 12 Nov every 4 weeks

    From 2nd May to 12th November, feed every 28 days with a nitrogen-rich fertiliser and keep the bed evenly watered. A steady feed helps the swollen stems bulk up without turning pithy.

  5. 05

    Harvest Swollen Stems

    13 Jun to 12 Nov

    Start lifting or cutting from 13th June once the swollen stems are about across and still tender. Pick over the crop through 12th November, because older plants soon become woody and splitting is more common after dry spells.

Companion plants

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

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 Kohlrabi to consider

Kolibri

Purple-skinned, reliable and quick to mature, with crisp white flesh and a good shape for the home garden.

Azur Star

A neat, purple variety that crops well in the UK and stays tender if picked promptly.

Quickstar

A fast, compact green kohlrabi that suits small gardens and gives an early crop.

Winner

A solid green variety with good standing power and dependable bulbs for summer picking.

Kohlrabi guides by town

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