Fruits (scroll down for vegetables and other foods)

Apples
Refrigerated apples last up to 10 times longer than those at room temperature. Apples emit ethylene, a naturally occurring gas that speeds ripening. To prevent apples from speeding up the ripening process of other items, store them in a plastic bag. To speed the ripening of bananas, place an apple in a bag of green bananas. Eat apples at room temperature.

Avocados
Keep unripe avocados at room temperature. To speed ripening, place in a paper bag with an apple or banana; to stop ripening, refrigerate for up to two days. Once cut, the flesh will brown rapidly. To prevent discoloration, sprinkle cut avocado with lemon or lime juice; if mashed (as in guacamole), press plastic wrap directly onto the surface.

Grapefruit
Grapefruit is ripe when picked and will not ripen further once off the tree. Grapefruit will last for several days if stored at room temperature. Otherwise refrigerate in a plastic bag or in the high humidity crisper section of the refrigerator where it will keep for several weeks

Kiwifruit
can be ripened at room temperature for 3 to 5 days. You can speed up the ripening process by putting kiwifruit in a paper bag with an apple, banana, tomato, or pear, all of which give off ethylene gas, which speeds up the ripening process. Ripe kiwifruit should keep in a refrigerator for 2 to 3 weeks.

Lemons
Lemons will keep on the counter at room temperature for a maximum of two weeks, depending on the temperature and humidity, and will keep in the refrigerator in plastic bags for up to six weeks. If you have extra lemons, squeeze and freeze the juice in ice trays and transfer cubes to plastic bags for long-term storage.

Mangoes
Store mangoes at room temperature and out of the sun, until ripened. The ideal storage temperature for mangos is 55 degrees F. When stored properly a mango should have a shelf life of 1 to 2 weeks. While the mango will not ripen in the refrigerator, it can be kept chilled there once ripe. Store cut mangos in a plastic bag for no more than 3 days.

Oranges
Oranges are best stored in a cool place outside the refrigerator and eaten within a few days. If you need to keep them longer, refrigerate in a plastic bag or in the vegetable crisper section of the refrigerator. As Valencia oranges ripen on the tree they will first turn a yellow-orange color and then regain a little green tinge near the stem end of the fruit, resulting from chlorophyll returning to the peel. This "regreening" of the orange is not a sign of immaturity or considered a blemish on the skin.

Pears
Ripen Bosc pears in a paper bag with an apple or a banana to speed the process. Bosc pears will have a sweet fragrance and yield to a gentle touch near the stem when ripe. Check pears in the bag daily and eat once they fit this description. You can refrigerate ripe Bosc pears up to 3 days.

Persimmons
Try not to buy more than you can eat in a short amount of time, as ripe persimmons can only be kept for up to three days. During that time, they should be refrigerated in a plastic bag - interestingly, the cold actually sweetens the fruit. To ripen a persimmon, place it in a pierced paper bag with an apple and keep it at room temperature.

Plums
Store at room temperature (between 51°F and 77°F) until fully ripened and ready to eat. To accelerate the ripening process place the plums in a paper bag along with a ethylene producing fruit such as a banana, apple or pear. Plums are ripe when they give off a sweet plum aroma and are soft to the touch. Once ripened, store the plums in the refrigerator until eaten but keep them away from ethylene producing fruit so they do not become over ripe.

Summer Fruits
Apricots, bananas, cantaloupe, kiwi, mangoes, nectarines, peaches, pears, and plums continue to ripen at room temperature after they are picked. To speed their ripening, put them in a loosely closed brown paper bag or ripening bowl at room temperature.

Vegetables

Acorn Squash
Winter squash or hard-shelled squash, such as kabocha and butternut, should not be refrigerated unless cut. Stored at 50°F to 55°F away from light in a well ventilated spot with low humidity, it will keep for up to three months. Cut squash will keep about one week when wrapped tightly and refrigerated.

Arugula
Best used fresh, but you can keep arugula for a few days in the refrigerator. Wash arugula, let it dry (use a colander or spinner). Place in a plastic bag and into the crisper drawer in the fridge. Sometime a paper towel in the bag helps to keep excess moisture to a minimum as well.

Beets
To store beets, trim the leaves 2 inches from the root as soon as you get them home. The leaves will sap the moisture from the beet root. Do not trim the tail. Store the leaves in a separate plastic bag and use within two days. The root bulbs should also be bagged and can be stored in the refrigerator crisper drawer 7 to 10 days.

Beet Greens Wash greens thoroughly in cold water and drain well. Refrigerate them in the vegetable crisper or in plastic bags or containers to prevent wilting and loss of nutrients. Use within 3 to 5 days.

Bell Peppers
Bell peppers like cool not cold temperatures, ideally about 45°F to 50°F with good humidity. Peppers are ethylene sensitive, so they should not be stored near ethylene-producing food such as pears or apples. Put peppers in plastic bags and they will keep up to five days in the refrigerator. Green peppers will keep slightly longer than the other, more ripe, varieties.

Bok Choy (Brassica rapa var. chinensis)
Wrap bok choy in a damp towel, or out in a plastic bag and place in the hydrator drawer of the refrigerator. Store for up to one week. Leaves will lose integrity and wilt if allowed to dry out.

Broccoli
Broccoli can be stored in the high-humidity vegetable crisper of your refrigerator for up to three days.

Butternut Squash
When stored in a cool, dark, dry, well-ventilated area, winter squash will keep for a month or more. The only time squash should be refrigerated is after it has been cut and wrapped in plastic.

Cabbage
Cabbage stored in a plastic bag in the refrigerator's humid vegetable bin will last at least a week.

Carrots
Before storing them remove their green tops, rinse, drain, and put the carrots in plastic bags and store them in the coldest part of the refrigerator with the highest humidity. They'll last several months this way. To keep the carrots crisp and colorful add a little bit of water in the bottom of the plastic storage bag; this will keep the carrots hydrated. Carrots should be stored away from fruits such as apples and pears, which release the ethylene gas that cause carrots to become bitter.

Celeriac
Celeriac can be kept refrigerated in a perforated plastic bag for up to 10 days. It cannot be frozen.

Corn
Corn is best eaten immediately. However, it can be stored in the refrigerator for a few days in plastic bags with the husk still on.  If possible, store in a refrigerator with a high humidity storage bin. If the corn has already been husked, partially or fully, refrigerate it in a perforated plastic bag.

Cucumbers
Should be stored in a plastic bag and placed in the refrigerator at a temperature between 45°F and 50°F for up to a week. Be sure not to wash cucumbers until you're ready to use them.

Eggplants and Mature Onions
Best kept moderately cool, about 10-15 degrees.

Garlic
Stored under optimum conditions in a dark, cool, dry place with plenty of ventilation, garlic will last from several weeks to one year. Try to use fresh garlic within a few weeks and do not refrigerate unless the garlic has been peeled or chopped.

Green Beans
Wash to add moisture and refrigerate in a plastic bag. Remove the tips (and strings, if present) right before cooking.

Fresh Greens:
Greens should always be washed thoroughly in lukewarm water to remove dirt that could stick to leaves. They can be wrapped in a damp paper towel, placed in plastic and stored in the refrigerator. If the towel is kept moist, they can keep for up to a week.

Lacinato Kale
Kale should be wrapped in a damp towel or in a plastic bag and refrigerated, preferably in hydrator drawer, for up to 1 week. Leaves will wilt if allowed to dry out. Plunge in cold water for 10 minutes to re-hydrate. Kale also freezes well, just blanche, squeeze out excess water and put into Ziploc and freeze.

Lettuce and Salad Greens
Greens will expire quickly if not stored properly. Greens like moisture and cool temperatures, so store lettuce in perforated plastic bags wrapped in damp paper towels, and keep in the refrigerator vegetable crisper. A good trick is to trim the bottom stem of whole lettuce heads as you would cut flowers then wash in warm water. Let the greens sit for 5 minutes to let dirt settle to bottom of sink then lift out lettuce. Spin or shake and paper towel dry before storing with the damp paper towel wrapped loosely around stem end and in an airtight plastic container or bag.

Mushrooms
If storing in the refrigerator, do not clean them before storing. Store uncleaned mushrooms in a paper bag or their original container. Do not store in plastic or airtight plastic containers, which causes them to retain moisture and decay faster. Keep them in the refrigerator for 3 or 4 days. It is best to eat them as soon as possible. Dried mushrooms may be stored indefinitely. To preserve mushrooms for an extended period of time, use other methods such as freezing, drying, salting, canning or pickling.

Parsnips
Store parsnips unwashed, in a loosely wrapped or perforated plastic bag in the crisper drawer of your refrigerator for 2-3 weeks.

Potatoes
Potatoes like cool (45°F to 50°F) humid (but not wet) surroundings, but refrigeration can turn the starch in the potatoes to sugar and may tend to darken them when cooked. Store in burlap, brown paper, or perforated plastic bags away from light, in the coolest, non-refrigerated, and well-ventilated part of the house. Under ideal conditions they can last up to three months this way, but more realistically, figure three to five weeks. New potatoes should be used within one week of purchase. Don't store onions and potatoes together, as the gases they each give off, will cause the other to decay.

Radishes
With the greens still intact, radishes should be immediately separated when you get home. Radishes will last up to two weeks inside a plastic bag in the crisper section of the refrigerator, but greens have a much shorter shelf life, only a few days. Keep both well chilled.

Snap peas
Snap and sugar peas have a somewhat longer shelf life than green peas, up to three days when kept refrigerated unwashed, in plastic bags.

Spinach
Untie bunches, remove any blemished leaves, trim off the stems, and wash it thoroughly in cold water. Repeat if necessary until you're sure all the grit is gone. Spin dry in a salad spinner or drain well, then put into clean plastic bags very loosely wrapped with paper towels. It will last only two to three days, so plan on eating your rinsed spinach right away. Cold, moist surroundings, as low as 32°F and about 95% humidity are the best for storing spinach.

Sunchokes (aka Jerusalem artichoke)
Even though this item is available year-round, the best season for sunchokes is from October to April, and they are best dug after a light frost. This vegetable can be eaten raw or cooked. Before eating or cooking, scrub the tubers thoroughly with a vegetable brush. Raw sunchokes should be stored in a cool, dry, well-ventilated area away from light. They can also be stored in the vegetable drawer of the refrigerator, wrapped in paper towels to absorb humidity and sealed in a plastic bag. Fresh raw sunchokes can be stored from 1 to 3 weeks. Cooked sunchokes should be refrigerated and consumed within two days.

Tomatillos
Fresh ripe tomatillos will keep in the refrigerator for about two weeks. They will keep even longer if the husks are removed and the fruits are placed in sealed plastic bags stored in the refrigerator. They may also be frozen whole or sliced.

Tomatoes
are similar to fruit when it comes to storage. Keep unripe tomatoes at room temperature. Place in the fridge to slow the ripening process when desired and after slicing.

Zucchini
Refrigerate in vegetable crisper in an opened plastic bag. They will remain firm for about one week. To avoid damaging the skin, do not clean zucchini until ready to use.

Other

Ginger
Tightly wrap in a paper towel or plastic wrap. It will keep in the refrigerator for 2-3 weeks. Or place ginger in a jar of sherry and it will keep in the refrigerator for 3-6 months.