How to Store Kohlrabi for Winter

Lift kohlrabi at golf-ball to tennis-ball size before the first hard frost, twist the leaves off without washing the bulbs, and pack them in shallow crates with slightly damp sand or similar at 0 to 4°C, checking every couple of weeks. Plan it as a short-to-medium store, not a spring store. Kohlrabi isn't a root: you are storing a swollen section of stem just above the soil line, which is why it doesn't behave like carrots or beetroot. One storage method in Garden Organic's guide covers kohlrabi along with true root crops, but no source gives kohlrabi a keeping time.

Why it doesn't store like a root

A carrot or beetroot is built to survive underground over winter as the plant's route to a second growing season, which is part of why they hold up in damp sand. Kohlrabi has no such strategy: the part you eat is a stem swollen just above ground level, with a short-term job of bulking up fast. The kohlrabi growing guide covers this: baby bulbs can be ready in about six weeks and full-size ones in about twelve, with a narrow harvest window at golf-ball to tennis-ball size (roughly 5 to 7cm across) before the texture turns woody, and the young leaves are cooked like kale soon after cutting. A vegetable bred for a fast life cycle doesn't gain months of shelf life just because it is cut from the plant. That is reasoning, not a measured figure, but it is why to expect kohlrabi to keep for less time than a true root crop.

Storage guidance

The RHS kohlrabi guide has no storage section, only kitchen advice: remove the outer skin, then grate or chop into salads and coleslaw, or steam, saute or add to stews. The RHS root vegetable storage page covers beetroot, carrots, celeriac, parsnips, salsify, scorzonera, swedes, turnips and winter radishes, and kohlrabi isn't on it. Garden Organic groups kohlrabi with carrots, parsnips, beetroot, turnip, swede and celeriac as storage organs of biennialA plant that completes its life cycle over two years: growth in year one, then flowering, seeding and dying in year two. Full definition → plants that store easily, and gives one method for the group: don't wash the crop, brush off excess soil, twist the leaves off close to the crownThe base of a perennial plant where roots and shoots meet, often sold and planted as a ready-made dormant plant rather than grown from seed. Full definition →, layer the bulbs in shallow crates or boxes with slightly damp packing material (leaf mould, sand, sieved soil, untreated sawdust or coir), and keep them very cool at 0 to 4°C. It gives no duration for the group.

Unlike a carrot or beetroot, the kohlrabi bulb swells above the soil, so mulchingA layer of material spread over the soil around plants to suppress weeds, retain moisture, and improve soil structure as it breaks down. Full definition → a row and leaving it in the ground doesn't work, and the soil isn't insulating the part you want to protect. Clamping buries a pyramid, so it is out for the same reason. A crate in a cool shed is the practical route. Swede is a long keeper grown in the same beds at the same time of year, but don't assume kohlrabi behaves like it: lift kohlrabi ahead of the first frost expected locally.

Step by step

1. Lift at golf-ball to tennis-ball size. Larger bulbs are already tougher and won't improve in storage.
2. Check each bulb. A split, soft patch, or slug or root-fly damage gives rot a way in once packed against sound bulbs. Use a damaged one in the kitchen straight away.
3. Don't wash them. Brush off soil by hand, since washing or scrubbing can damage the skin.
4. Twist the leaves off close to the crown and use them straight away.
5. Pack in a shallow crate with slightly damp sand, sieved soil, leaf mould, untreated sawdust or coir between the bulbs.
6. Store at 0 to 4°C in a shed, unheated garage or cool cellar: cool enough to slow the bulb, not cold enough to freeze it. An unheated shed can drop below that in a hard cold snap, so check the crate then.
7. Check every couple of weeks. Treat it as a short-to-medium store and don't pack it away until spring.

No humidity target is given. Damp, not wet, packing does the work, and the checks below tell you if the balance is right. For a small amount you'll use soon, an unwashed, trimmed bulb in the fridge crisper drawer works the same way. For longer keeping, freezing (peeled, diced, blanchedExcluding light from part of a growing plant, usually by earthing up, wrapping or covering, so it grows pale, tender and less bitter. Full definition → briefly, cooled and bagged) or pickling is more reliable than the crate, so consider that for part of the harvest rather than committing it all to a shed with no stated shelf life.

Timing against first frost

Lifting before a hard frost matters as much as the method, since a frosted bulb is a poor candidate for keeping. Typical first autumn frosts from the frost dates page, built on Met Office station data:

Checking the crate

With no benchmark for how long kohlrabi should last, checking is the main safeguard. Soft bulbs that give when pressed are breaking down, so remove them before they affect neighbours. Sprouting means the bulb is past its best and should be used immediately. Mould on the packing means it has gone from damp to wet, so refresh it if it feels sodden. Shrivelling means the store is too dry or too warm: move the crate somewhere cooler and more humid.

Common questions

Sources