Interactive lesson

Clamps and earth pits, step by step

Interactive lesson: winter stores without a cellar — a clamp for potatoes, cabbage and roots, an earth pit, a buried barrel, lifting stores in midwinter and safety.

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The whole lesson as text

1. Clamp, pit or barrel

The earth is the oldest fridge: a clamp keeps potatoes at 3–6 °C (37–43 °F) all winter.

A clamp for large amounts — A long mound of straw and soil. One metre of clamp 1.2 m wide and 0.8 m high holds roughly 250–300 kg of potatoes.
Earth pit — For carrots, beetroot, celeriac and root parsley: roughly 20–100 kg, a small pit in the garden.
Buried barrel — A clean 200 L (55 US gal) barrel holds roughly 50–70 kg of roots with sand, protected from mice.
Bed under straw — Parsnips, root parsley, carrots, leeks and horseradish can stay in the ground where they grew, under 20–40 cm of straw. Mark the ends with pegs.

Why: A clamp costs nothing but straw and work, and can hold a tonne of potatoes. The earth pit and the buried barrel are its small cousins, for a backyard and ten-odd kilos of carrots and beetroot.

Potatoes for winter and spring go in the clamp, potatoes for 3–4 weeks in the cellar; the clamp is opened once or twice a month.
If a clamp would be longer than 8–10 m, make two shorter ones: they are easier to cover and open.

2. Site and ground

Water is a clamp's worst enemy, so you choose the site before anything else.

Dry and raised — A gentle rise or level ground where water doesn't stand even in March. Never in a hollow.
Shelter from wind — Against a wall, hedge or shed, on the north or east side.
Close to the house — You open it in midwinter, in snow: the path to the clamp must be passable.
Pegs and ditch — Cut the grass, peg out the clamp, 1–1.5 m wide at the base. Dig a ditch 20–30 cm deep round it, falling to one side.

Why: A clamp in a hollow or without a ditch fills with snowmelt and the potatoes rot. On a sunny south side the clamp warms up in March, and voles live by hedge bottoms and stone heaps.

Don't build the clamp on last year's spot: rot residues and mice stay in the soil.
In wet, clay soil build the clamp on the surface, even slightly raised on gravel or brushwood covered with straw.