Root cellar: the original frost-free `refrigerator'

March 15, 1988

For gardeners who feel that nothing tastes quite so good as home-grown, root cellaring is an old idea that extends the pride and pleasure of gardening year-round. It also avoids the tedious and more expensive process of canning or freezing food - often with second-rate results.

The cold, dark root cellar of yesteryear, necessary in an age when refrigeration was unknown, evokes images of a rich store of abundance, good food heaped up for a long harsh winter ahead.

Today's root cellar, though no longer so romantic an image, is also a cold-storage area used to keep fruit and vegetables fresh for months after they are picked.

It may be as crude as a pit, or as simple as a well-mulched barrel dug into the ground. It may be as picturesque as a stone-faced room with a grass roof dug into the side of a hill, or as convenient and effective as a well-insulated room - with temperature and humidity control - built into a corner of a modern basement.

A bowl of steaming-hot vegetable soup on a cold winter day is even more delightful when everything comes from the summer garden via a root cellar. Fruit and vegetables will last there for predictable lengths if properly stored.

A good variety of soup vegetables - root crops, summer and winter squash, cabbage - will be good to eat well into winter. Onions, garlic, and potatoes often last into the next growing season. Apples will also last well into winter.

Kohlrabi, celery, and Chinese cabbage will store well for two to four months. Some produce - cauliflower, citrus fruit, cucumbers, eggplant - will last only a month or two in storage. But they may do better in a somewhat humid root cellar than in a refrigerator. And some produce is just too perishable for storage purposes.

The best type of root cellar for you depends on a number of variables - including climate, length of growing season, existing resources, personal preferences, economic resources, quantity and kinds of produce to be stored, and the importance of convenience.

We chose to build a basement root cellar because of climate, convenience, and near-perfect construction conditions. It is a modern re-creation of the excellent cold, humid food-storage areas that were found in older homes with dirt-floor cellars before the days of central heating and tightly sealed concrete basements.

The basement root cellar is essentially a dark, insulated, well-ventilated room built to keep the cold and humidity in and the heat out.

Ideal storage conditions include a temperature of 35 to 40 degrees F. with a humidity of 85 to 90 percent - which is much colder and more humid than the average basement. Although good air circu-lation is always important, the ideal temperature range can be achieved by opening and closing air vents according to outside air temperatures.

Moisture from the produce naturally creates a high humidity, which can then be augmented by a number of simple methods such as using pans of evaporating water or a tub of damp sand or gravel.

The best location for construction is in a northeast corner with an existing window, an electric light, and no plumbing or heating pipes. With these conditions, only two walls need to be built, and venting to the outside is simple.

Adaptations for less than the ideal location can be made, but at least one wall must be a cool outside wall. Our root cellar is in a southeast corner. Though it works well, it is exposed to more of the sun's warmth than is desirable.

Construction is easy and inexpensive if a corner site is used. With very limited carpentry skills, I built our 8-by-8-foot root cellar in an almost ideal corner, using higher-quality (sale!) materials than necessary, for about $200.

The size is more than adequate for what a family of four can eat, while providing flexibility for new storage uses as they develop - dahlia bulbs, fruit bought at bargain prices, uprooted geraniums, etc.

Last fall, we started out with over 1,000 pounds of home-grown vegetables in storage. Winter squash, pumpkins, and sweet potatoes were properly cured before being stored in the warmer, drier basement. Everything else went into the root cellar neatly arranged on wooden shelves, packed in half-bushel baskets or wooden boxes, or replanted in soil (celery and Chinese cabbage). Produce that loses moisture easily was packed in damp sand, sawdust, newspaper, leaves, or plastic bags.

As you gain experience in root cellaring and discover what works best for you, there will be less and less spoilage. Normally, with the exception of erratic spoiling of winter squash and pumpkin, we have very little spoilage and can eat just about everything by spring. If there is excess, vegetable gifts out of season are welcomed by friends.

Libraries, bookstores, magazines, and agricultural extension agents have good information on the storage requirements of individual fruits and vegetables. They also have ideas on root cellar construction and on how to decide what type of root cellar will work best in your particular situation and climate.