Store Vegetables for After-Season Use

In addition to being canned or frozen, some vegetables can be stored without refrigeration to extend the season from one week to several months. Proper handling and storage conditions are important, however.

Crops such as potatoes, carrots, beets, parsnips, cabbage, onions and winter squash may be kept for several months, whole tomatoes, peppers, cucumbers and snap beans may be kept for a shorter period. Some vegetables require temperatures close to 35 to 40 degrees with high humidity for storage. These include root crops such as potatoes, carrots, beets, turnips and leaf crops such as cabbage and Chinese cabbage. Indoor space with these conditions is not normally available to the home gardener, but he can easily make small outdoor storage units.

If only a small quantity of produce needs to be stored, outdoor cone-snaped storage units may be the answer. To make the storage unit, first spread a layer of straw, leaves or other litter on the ground. Stack the vegetables in a cone-shaped pile in the center of this area. Cover the pile of vegetables with a layer of straw, and then cover the straw with three to four inches of soil. Firm the soil by tapping with the back of the shovel to make the cone of soil waterproof and to prevent erosion.

Small pits do not need outside ventilation, but if the pit is fairly large, place two or three boards vertically through the center of the pile to form a flue. Cap the flue with two pieces of board nailed together at right angles. Once a pit is opened, the entire contents should be removed. Therefore, it is better to build several small pits rather than a single large one. Put a small quantity of all vegetables in each pit. Dig a shallow drainage ditch around each storage cone when it is completed. Any accumulation of water inside the cone can ruin the vegetables.

Tomatoes, peppers, sweet potatoes, pumpkins and squash may not be stored in this way. Temperatures are too cool, and damage may result. To store tomatoes, bring them indoors just before the first killing frost. Harvest the large, mature green tomatoes for storage. Small immature tomatoes will not ripen well. Wrap the tomatoes in newspaper, and stack them in shallow trays no more than two layers deep. Green tomatoes will ripen about two weeks if kept at 65 to 70 degrees. At 55 degrees they will ripen about four weeks. Do no keep them cooler.

Green peppers may be stored in the same way for about two weeks. Since they are more subject to drying, cover them loosely with plastic to reduce moisture loss. Sweet potatoes may be kept until April or May. They should be dug before frost and cured at about 80 degrees for 10 days. After that time, store them at temperatures between 55 and 60 degrees. Sweet potatoes are subject to chilling and will begin to rot if kept at temperatures below 50 degrees.

http://www.extension.umn.edu/distribution/horticulture/DG1424.html