- Harvest the highest quality fruits, roots, tubers, stalks, heads, or bulbs at the optimal time;
- Handle carefully to avoid bruising and cure as necessary before storing
- Place in the appropriate storage environment, depending on the requirements of the specific crop.
Cooking and eating fresh from the garden is one of life's great pleasures. Continuing to enjoy your home-grown produce during the depths of winter however, can be equally as satisfying, and easily achieved by following a few simple steps.
Crops that are strictly eaten fresh such as lettuce or specialty greens, or that store for only 2-3 weeks (beans, peas, corn, tomatoes, peppers, eggplant, cucumbers, melons, broccoli, cauliflower, leeks, okra, and summer squash) will not be considered here. Most of these vegetables can be preserved by freezing, canning, pickling, or drying. Instead, we shall discuss only those vegetables that can be maintained for many months in the fresh, whole state. These include the root crops (beets, carrots, parsnips, radishes, rutabagas, turnips), potatoes, garlic, onions, pumpkins, winter squash, cabbage, and celery. Root Crops:
The simplest and least expensive method of root storage is to leave the crop in the ground, harvesting as needed throughout the winter. In warm climates where minimum temperatures rarely fall below 30º F (Zone 10), roots will continue growing slowly throughout the winter and no additional mulch is needed. In moderately cold areas where minimum temperatures are 10-15° F (Zones 8-9), root growth will stop, and applying a thick layer of straw mulch or an insulating blanket will protect the roots from freezing and will keep them firm and fresh for several months. At minimum air temperatures below 10° F, it is best to dig up your crop before the ground freezes and store it in a root cellar. Heavy mulching (i.e. a foot or more of straw) can prevent the ground from freezing for up to a month after exposed areas have frozen. If you have gophers or other ground dwelling pests however, you may want to remove your crop as soon as it is mature because these critters won't leave much for you to store.
While young roots are usually more tender and delectable, medium to large roots hold up better in storage and are often more nutritious. Therefore, plant your seed early enough in the summer to attain maturity by the time growth ceases in the fall. Store only whole, unblemished roots. The splits, insect-gnawed, or slimy specimens should be consumed immediately (not the slimy ones!) or composted. Never wash roots before putting them in storage, as this will make your roots susceptible to fungal growth. Instead, harvest when the soil is moist (not wet), and remove excess dirt with your hands or a rag. Clip off the green tops about an inch above the top of the root. It is best to prepare your roots in the shade to prevent the root surface from drying out.
How you store roots at this point depends upon the humidity and temperature of your storage area. Ideally, a room should maintain a very high relative humidity (95-98%) and a constant temperature of 32-35° F.
If you have a room with these conditions, put your roots into sturdy 25 pound capacity plastic bags with several vertical slits to provide ventilation. Then put a couple of handfuls of coarse, clean wood chips into the bag to absorb excess moisture. Finally, store the bags on preferably metal or plastic mesh shelving as wood shelves can absorb moisture and become moldy. If necessary, periodically pour a bucket of water on the floor to maintain the high humidity. If you have a cool room (32-40° F), but the humidity is less than 90%, it will be necessary to store your roots in moist sand in a sturdy plastic or wooden bin to prevent them from drying out. Potatoes:
This year-round staple food is actually a tuber (an underground stem) rather than a root, and it requires a different set of conditions than the root crops. Using a spading fork or a broad fork, harvest your tubers before hard fall freezes occur, but after most of the foliage has died back. Again, rub off excess dirt, but do not wash them. Potatoes require an initial curing period of about two weeks to prepare them for long storage. Place them in a room at 50-60° F and 85-95% relative humidity. This helps heal bruises and wounds on the surface of the potato and minimizes shriveling and rotting later on. After this two week curing, pack your tubers loosely in bags or boxes and lower the temperature to around 38-40° F or move them into an area with this temperature range. Every couple of weeks throughout the winter you should inspect the potatoes. If they begin sprouting the temperature is too warm; if they begin shriveling the humidity is too low; and if rot sets in the humidity is too high.Onions & Garlic:
Bulb crops, such as garlic and onions, need to be cured to reduce water loss and decay during storage. When at least a third of the garlic leaves have become brown, and when nearly all the onion tops have died back, dig up the bulbs with a spading fork and remove excess dirt from the roots. Then place them on racks or hang in bundles or braids out of the sun and allow them to dry for 1-2 weeks. This enables the outer leaves of the neck to form dry scales, preparing them for storage. Always remove decayed bulbs before curing and storage to ensure a greater percentage of usable product after storage. After curing, remove loose dirt and skin, clip the tops to about one inch above the bulb, trim off the roots, and place in netted bags. Soft neck garlic and some onions can be left in braids.
The Alliums store best in cool conditions like the roots (32-35° F) but need to have much lower humidity (50-75%) or they will rot. Therefore, if you are storing all your vegetables in a room that is better suited for the bulbs, the root crops need to be stored in boxes filled with moist sand rather than on open shelves. If you do not have a cool cellar, you can store your onions and garlic in a space with moderate room temperatures (65-75° F) for several months. The main concern is that if the relative humidity is too low the bulbs tend to shrivel up, so you may need a humidifier if you live in a dry climate or your house is excessively dry in the winter. Winter Squash:
Harvest only fully ripe squash for storage. If your thumbnail cannot penetrate the skin the fruit is mature. There is no hurry to harvest winter squash and pumpkins since they cannot over-ripen on the vine, though you'll want to pick the mature fruit before the first hard frost. Upon harvesting, leave a few inches of stem attached, and handle with care to avoid bruising, which can greatly reduce storage life.
Winter squash and pumpkins must be cured in a warm, well-ventilated place for about ten days to dry and harden their skins before storing. Look for a spot, in the greenhouse, on a sunny porch, or by a woodstove where the temperature ranges between 75-85° F.
Ideal long term storage conditions for winter squash is in a cool, dry place, approximately 50-60° F and 50-75% humidity, with moderate air circulation. A basement or an attic with a fan may be the perfect place. Set the fruits securely on shelves, so they are not touching one another. Different varieties have different shelf lives. Catalog and pack descriptions will identify the best keepers. Cabbage & Celery:
Cabbage and celery are about the only "green" vegetables that hold up in storage. At harvest, cabbage heads should be full and hard, and celery stalks large and succulent. For both, dig up the whole plant including the roots and place them in a bucket filled with moist soil in your root cellar and water regularly. Celery stalks can be harvested continuously through the winter. The cabbage should be harvested as a whole head and the outer wrapper leaves will need to be removed. After the tops of these plants have been harvested, the buckets they were planted in can be brought to a sunny spot or a greenhouse where the roots will sprout new green growth.
Cabbage may also be handled in two other ways. The first would be to cut the roots off immediately upon field harvesting, wrapping the heads in newspaper and then placing them on a shelf in a moist (90-95% relative humidity) and cool (32-35° F) room. The outer leaves would need to be removed before eating, but the heads may keep for up to 4 months in these conditions. The second method would be to leave the roots on the plant and hang the whole plant upside down in that same cool, moist room, and storage life would be even longer than with the first method. Good cabbage for storage is January King and Red Drumhead, and all varieties of celery store well.
By harvesting ripe, and handling and storing your produce according to the specific needs of each crop, you should be able to enjoy summer’s bounty all winter long. Combine these simple storage practices with canning, freezing and other preservation techniques, and you can approach year-round food self-sufficiency from the garden.