Apples
Apples emit ethylene, a naturally occurring gas that speeds ripening. To prevent apples from speeding up the ripening process of other items in your produce drawer, store them in a plastic bag. Conversely, if you want to speed up the ripening of bananas (or any other ethylene sensitive produce) you can place an apple in a bag with the bananas. Refrigerated apples last much longer than those left at room temperature. To maximize an apple's flavor, let it come to room temperature before eating it.
Avocados
Hard avocados ripen at room temperature in three to six days. To speed up the process, place them in a paper bag, preferably with an apple. Storing unripe avocados in the refrigerator will keep them from ripening. Keep your ripe avocados in the refrigerator and use within two to three days.
Bananas
Keep bananas at room temperature until ripened. Once ripened, bananas can be refrigerated for 3-5 days. Over ripe bananas can be put in freezer in a plastic bag and used for smoothies (still frozen) or banana bread (thawed).
Berries
Store unwashed berries in the refrigerator. Use quickly, as fresh organic berries are not sprayed with anti-fungal agents. They spoil quickly! Cranberries, however, have a longer shelf life than other berries. Strawberries are extremely perishable and should be refrigerated immediately. Store unwashed strawberries in the refrigerator by stacking them on paper towels (between the layers as well), in a moisture-proof container. Eat them within 48-72 hours, or freeze them. Most berries freeze nicely, and will keep up to ten months in the freezer. To freeze berries, rinse gently and dry them in a colander or on paper towels. Then, put them on a sheet pan or tray in the freezer for one hour. Once frozen, store them in a freezer bag/container. This method will prevent them from sticking to one another and makes them easier to measure out for future needs.
Cherries
Cherries are very perishable, and they should be refrigerated in a plastic bag. Before eating them, let them come to room temperature as the flavor is much better.
Citrus
Oranges keep well in the refrigerator. Oranges can also be stored at room temperature, though they will not last as long. Oranges also yield more juice when stored at room temperature. Keep lemons and limes in the refrigerator. Grapefruit can be stored at room temperature if they are to be used within three to five days. They are juiciest when warm rather than chilled. For longer storage, they should be stored in the refrigerator crisper. Short-term, tangerines/tangelos will keep well at a cool room temperature. For longer-term storage, keep them in the refrigerator.
Kiwi Fruit
It is best to store kiwis in the refrigerator. To make them ripen faster you can keep them in a closed plastic bag together with an apple or pear.
Mangoes
Store mangoes at room temperature for even ripening. Ripe mangoes will keep for a couple days in the refrigerator. Haitian and Ataulfo mangoes will be soft and may have a wrinkly skin when they are ripe.
Melons
Ripe melons should be stored in the refrigerator. Unripe melons can be kept in a cool dark space until properly ripened. Cut melons should be wrapped tightly in plastic. Leave the seeds inside a cut melon until you're ready to eat it to help keep the moisture in the fruit.
Pears
Pears actually ripen best once they are removed from the tree, and are usually picked before they reach their peak ripeness. Keep pears at room temperature for best flavor and even ripening. If you want to keep them a few days longer, store them in the refrigerator.
Pineapple
Pineapples ripen best at room temperature. Store them leaf side down, for even ripening. Once ripened pineapples can be stored in the refrigerator for a couple days.
Stone Fruit (Apricots, Peaches, Nectarines, Plums)
Store ripe stone fruit in the refrigerator and use promptly! Apricots should be stored at room temperature until they are ripe. Once ripened should be stored in a plastic bag in the refrigerator. They are very perishable!
Tomatoes (Cherry, Grape, Plum, Roma, Salad)
Keep tomatoes at room temperature until ripened. Once ripened, tomatoes will last for a few days. Try to avoid refrigerating tomatoes whenever possible, as it severely affects their flavor.
Thanks to Nature's Garden, Woodend for these tips.