By late autumn a German vegetable plot has usually given up most of its tender crops, and what remains — carrots, beetroot, celeriac, potatoes, leeks and the cabbages — is exactly the produce that stores well. The task shifts from growing to keeping. Done carefully, a single harvest can supply the kitchen well into the following spring.
Carrots, beetroot and celeriac in sand
The classic method for firm roots is packing them in damp sand. The sand holds humidity against the roots so they stay crisp, while keeping individual roots from touching and passing on any rot. To do it:
- Lift the roots on a dry day, twist or cut off the tops leaving a short stub, and brush off loose soil — but do not wash them.
- Lay a bed of slightly damp sand in a box or crate.
- Set the roots in so they do not touch, then cover with more sand and repeat in layers.
- Keep the box in a cool, frost-free cellar and check the sand stays just barely damp.
Beetroot and celeriac take the same treatment. The aim throughout is firm roots that never freeze and never dry out.
Potatoes: cool, dark and never frozen
Potatoes have two firm rules. First, keep them in complete darkness — light turns the skins green and that green tissue is best not eaten. Second, keep them cool but above freezing; if potatoes get too cold their starch turns to sugar and they taste sweet and cook poorly.
Store potatoes in paper or hessian sacks, or in ventilated wooden crates, somewhere dark and cool. Sort out any that are cut or soft before they go in, and look through the store every few weeks.
One bad one spoils many
The single most useful habit in vegetable storage is the regular sort-through. Soft rot and mould spread from item to item, so removing one spoiling potato or carrot early can save the rest of the box. Inspect stored produce every two to three weeks.
Cabbages and other brassicas
Firm winter cabbages — white and red storage types in particular — keep for a remarkably long time. Cut the heads with a few outer leaves left on, and keep only those that are solid and unblemished. There are two common approaches:
- Cellar hanging or shelving: stand or hang whole heads in a cool, humid cellar with space around each for air to move.
- The earth clamp: heads can also be stored in an outdoor clamp, described below, where the ground frost is kept off them.
Leeks are hardy enough to be left in the ground in much of Germany and lifted as needed, though a hard frozen soil makes that difficult; some gardeners heel a supply of them into a box of soil in the cellar instead.
The outdoor clamp (Erdmiete)
Where there is no cellar, the traditional clamp keeps roots through winter outdoors. In essence it is a heap of roots on a bed of straw, covered first with more straw and then with a layer of soil thick enough to keep frost out. A wisp of straw left poking through the top allows a little ventilation. The clamp is opened from one end as needed, and resealed.
Clamps suit potatoes, carrots, beetroot and storage cabbages. The main risks are rodents tunnelling in and frost reaching the produce in a severe winter, so the covering needs to be generous and the site well drained.
Bringing it together
Each crop wants slightly different conditions, but the constants are a cool temperature above freezing, the right humidity for the crop, and regular inspection. For the structures that provide those conditions, see the notes on building and maintaining an earth cellar; for getting produce ready before it goes into store, see preparing the autumn harvest for storage.