When to Harvest Kohlrabi — Signs, Timing & Storage

Getting the harvest moment right is the difference between a kohlrabi you look forward to eating and one you wish you had picked a week earlier — or a week later. Pick too early and you lose size and flavour; pick too late and you lose texture, sweetness and storage life. This guide covers the signs to look for, the right way to pick without damaging the plant, the best time of day to harvest, how often to pick, what happens if you leave the crop too long, and how to store it once it is in.

Kohlrabi looks like a vegetable from another planet — a swollen stem sitting above the soil like a little green sputnik — and its harvest rule is wonderfully simple: pick it small. A kohlrabi the size of a tennis ball is crisp, sweet and tender; one left to grow to the size of a grapefruit is woody, fibrous and fit only for stock. Size is everything, and the tape measure is your eye.

Kohlrabi at a glance

Growing factor What kohlrabi need
Days to maturity 50–60
Category vegetable
Family Brassicaceae
Cold tolerance frost-tolerant
Water needs moderate

The figures above come from our crop data, which draws on standard public horticultural references. They are broad published ranges, not exact figures — the real timing in your garden depends on your variety, your soil and your weather. Use the harvest-date calculator to work out your expected harvest date from your sowing date, and check your local extension service for dates that fit your climate.

How to tell when kohlrabi are ready

A kohlrabi bulb is ready when it is about 2–3 inches across — roughly tennis-ball size — with smooth, unblemished skin, a firm feel and fresh green leaves on top. The skin should be taut and glossy for green varieties or purple for purple types, and the bulb should feel heavy and solid. Squeeze it gently: it should be firm all over, with no soft spots or cracks. Leaves that are yellowing or a bulb that is splitting are signs it has been left too long.

  • Bulb about 2–3 inches across — tennis-ball size — for the tenderest eating.
  • Skin smooth, taut and unblemished, with no cracks or soft spots.
  • Bulb feels firm and heavy when squeezed gently.
  • Leaves fresh and green; yellowing tops or splitting skin mean it is overmature.

When to harvest kohlrabi

Kohlrabi takes 50–60 days to mature and is a frost-tolerant, cool-season crop, best sown in spring and late summer for autumn. It grows fast, so start checking the bulbs from about six weeks after sowing and expect the harvest window for one sowing to last two to three weeks. Check your local extension service for sowing dates, since a crop timed for cool weather is sweeter and less likely to bolt.

How to pick kohlrabi without damaging the plant

Cut the bulb from its stem with a sharp knife, slicing just below the bulb and leaving the leaves attached until you are ready to use it — the leaves help keep the bulb fresh. Or pull the whole plant and trim the stem and leaves at home. The leaves are edible too, cooked like other brassica greens, so do not throw them away. Peel the bulb before eating: the skin is tough even on young bulbs.

If you are still learning the crop, our growing guide for kohlrabi covers the whole season from sowing to harvest, and the planting calendar for zone 5 shows the timing for a mid-range climate — adjust earlier or later for your own zone.

The best time of day to harvest

The best time to pick kohlrabi is in the morning, after the dew has dried but before the heat of the day builds up. In the cool of the morning the plant is full of water from the night, the leaves and stems are crisp, and the harvest is at its freshest — a kohlrabi picked at 8 in the morning will be noticeably crisper than one picked at 3 in the afternoon. Morning picking also means the crop goes into the kitchen or the refrigerator while it is still cool, rather than sitting in a warm basket losing moisture. Avoid picking in the heat of the day, when plants are wilted and stressed, and avoid picking when the plants are soaking wet from rain or heavy dew, since wet foliage spreads disease and wet produce spoils faster in store. If you must pick later in the day, pick in the evening shade instead, and get the harvest cooled quickly.

How often to pick kohlrabi

Pick bulbs as they reach 2–3 inches, taking the largest first and leaving smaller ones to size up. A row picked this way gives a steady supply over two to three weeks. Pick promptly — a bulb can grow from perfect to woody in a single warm week.

What happens if you leave kohlrabi too long

Left too long, kohlrabi turns woody and fibrous, the skin cracks, the flavour coarsens and the bulb can go hollow in the middle. Oversized bulbs are also more likely to split after rain. A woody kohlrabi cannot be rescued by cooking, though it can still be used for stock — so pick on time and compost the failures.

How to store kohlrabi

Short-term storage

Trim the leaves, wrap the bulb in a bag and refrigerate for two to three weeks. The leaves should be used within a few days, like other greens.

Longer-term storage

Kohlrabi stores for months in a cool, dark place layered in damp sand, like other root vegetables, or sliced and frozen after blanching. It is a good keeper for a brassica, as long as it was picked young and firm.

If you are growing a lot of this crop, the vegetable yield estimator helps you work out how much you are likely to harvest, so you can plan your storage — and your preserving — before the glut arrives.

Succession and continuous harvest

Sow kohlrabi every three to four weeks in spring and autumn for a continuous supply. It is fast and compact, so it fits well between slower brassicas and in gaps left by harvested early crops.

Common harvesting mistakes

  • Waiting for a big bulb — the sweetest kohlrabi are picked at 2–3 inches across.
  • Letting the soil dry out, which makes bulbs woody and liable to split.
  • Forgetting to peel the bulb — the skin is tough even when young.

Frequently asked questions

When is kohlrabi ready to harvest?

When the bulb is about 2–3 inches across — tennis-ball size — firm and smooth-skinned. They mature in 50–60 days from sowing.

What happens if kohlrabi gets too big?

It turns woody, fibrous and hollow, and the skin cracks. Pick bulbs small for crisp, sweet eating, and use oversized ones for stock.

Do I peel kohlrabi before eating it?

Yes — peel the tough skin off first, even on young bulbs. The flesh inside is crisp and sweet, raw or cooked.

Can I eat kohlrabi leaves?

Yes — the young leaves are edible cooked like other brassica greens. Use them within a few days of picking.

How long does kohlrabi keep after picking?

Two to three weeks in the refrigerator, or months layered in damp sand in a cool, dark place. Slice and freeze it after blanching for longer keeping.

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