I know how root vegetables like potatoes, carrots and beetroot were stored successfully for months in the early 1900s because my husband's father explained it to him. Additional information has been supplied by Bill Hogg. The same method was probably used for centuries.
See also the page on preserving runner beans.
The gardens were small on the estate of Victorian terrace houses where my mother grew up in the early 1900s, but the men did have allotments, and although much of what they grew would have been eaten fresh, they would have stored what was left over from a good yield.
The method of preserving the root vegetables was known as 'clamping' and it involved storing the vegetables in what was known as a 'clamp'. The principles were:
An old-style clamp for storing root vegetables.
If possible choose a site that is likely to be reasonably dry, although this is not always possible.
Start by digging two trenches and putting the soil in a line between them as shown in the diagram. The lengths of the trenches must depend of the amount of vegetables to be stored. In earlier times, men probably had a 'feel' for this, and they could always make the trenches longer if necessary.
The trenches are for drainage and the raised soil is to keep the vegetables above ground level away from ground water and frost.
Spread a layer of straw along the raised area and layer the vegetables on it
Continue with more layers of vegetables, letting them dry between layers but not dry out. Then top with straw and more soil.
I am told that clamping vegetables was a task given to prisoners of war during World War Two. Pat Cryer
The resulting clamp should be of pyramid cross section and about a metre high. This size is important because the moist straw causes a form of decomposition to take place which provides enough warmth to keep the clamp from freezing even in cold winters. If the clamp is too small, it does not keep sufficiently warm and if it is too large, the vegetables get too hot and start to rot. So larger clamps need to be longer rather than wider.
The vegetables are removed as required, starting from one end of the clamp and working towards the other end. This maintains the optimum cross section of the clamp.
The vegetables can then be cooked in the usual way.
This page describes how people in the early 1900s (1900's) stored root vegetables for use in winter.