Potatoes and Onions Keep 2 to 4 Weeks Out of the Fridge in a Cool, Dark Spot

Not every vegetable belongs in the refrigerator. Potatoes, sweet potatoes and onions keep 2 to 4 weeks when they are stored in a cool, dry, well-ventilated spot away from light, according to University of Maryland Extension.

The same guide says tomatoes and uncut melons should stay at room temperature, too. With holiday cooking about to fill every shelf, knowing which produce can skip the fridge frees up space and keeps flavor and texture where they should be.

Potatoes and Sweet Potatoes: 2 to 4 Weeks

The University of Maryland Extension’s guide to storing garden fruits and vegetables puts potatoes and sweet potatoes in the room-temperature group, with a storage life of 2 to 4 weeks in a cool, dry, well-ventilated area away from light. The guide also recommends scrubbing them before cooking rather than before storing. When the peeling starts, the scraps belong in the trash or compost, and a list of the things never to put in a garbage disposal before Thanksgiving cooking is worth a look before the big meal.

The University of Idaho explains why temperature matters. Most homes run at 65 to 75 degrees Fahrenheit, warmer than potatoes prefer, and its extension publication “Options for Storing Potatoes at Home” recommends a cool spot of 42 to 55 degrees. Warm storage speeds up sprouting, which can begin anywhere from 30 to 140 days after harvest depending on the variety.

The refrigerator brings its own problem. Idaho researchers found that cold storage converts some of a potato’s starch to sugar, which produced the darkest color in fried potatoes during their testing. Baked and boiled potatoes are less affected, but home cooks planning fries or roasted wedges will see the difference. Light is also a concern: it turns potatoes green, and the publication notes that the green color does not fade once the potato is back in the dark, so a dark cabinet or pantry bin is the better home.

A pantry shelf set aside for root vegetables is an easy project to fold into broader kitchen organization ideas, especially when the goal is a dark, airy corner away from the stove. A basement or garage shelf can work too, and these best practices for seasonal storage cover how to keep a shared storage space orderly.

Onions: Cool, Dry and Airy

Onions share the same 2- to 4-week window in the Maryland guide, with the same cool, dry, ventilated conditions. Potatoes are different on one point: they are about 80% water and dry out in very dry air, the Idaho publication notes, which is why it suggests perforated plastic bags rather than airtight containers for them.

The University of Minnesota Extension adds that properly dried onions should be stored in a cool, dry area where they will not freeze, and that they will start to sprout if kept above 40 degrees, according to its guide to growing onions. Home gardeners drying their own harvest are told to keep onions in a warm, well-ventilated place for two to four weeks until the outer scales are dry and the neck is tight.

The onion is the most widely cultivated species in the Allium genus, which also includes garlic, leeks and chives, according to Wikipedia’s entry on the onion. Gardeners extending the season can also look at elevated garden beds for fall greens and herbs, and cooks who want fresh flavor all winter can start a row of the kitchen herbs that keep growing on a sunny windowsill.

Tomatoes and Uncut Melons Stay on the Counter

Tomatoes often end up in the fridge, but the Maryland guide says tomatoes should be kept at room temperature, and that refrigeration makes them lose flavor and become overly soft. To speed ripening, it suggests a paper bag.

Uncut melons follow the same rule. They should stay at room temperature until ripe, the guide says, and the rind should be scrubbed well, preferably with a brush, before cutting. Once a melon is cut, it moves to the refrigerator, where it keeps 3 to 4 days covered.

Peaches, pears and nectarines take a middle path. They ripen at room temperature first, then go into the refrigerator in plastic bags, where ripe fruit keeps about 5 days, according to the Maryland guide.

Winter Squash and Pumpkins Last Longest

For long-term storage, winter squash outlasts nearly everything else on the list. The Maryland guide says winter squash keeps up to 3 months in a cool, dark place, depending on its size and variety, while a whole pumpkin keeps up to 1 month. Both should have their outsides scrubbed before cutting. Winter squash is picked at maturity, once its skin has hardened into a tough rind, and at that stage most varieties can be kept for use through the winter, according to Wikipedia’s entry on winter squash.

That makes squash and pumpkins a natural fit for a garage shelf or basement corner during the colder months. The cool, dark conditions the Maryland guide calls for are easier to find there than in a heated kitchen.

What Does Belong in the Crisper

Plenty of produce still needs the cold. The Maryland guide says beets, carrots, parsnips, radishes and turnips keep 1 to 2 weeks in the crisper with their green tops removed, ideally in mesh bags. Berries keep 2 to 3 days unwashed in containers, and salad greens keep 2 to 4 days when refrigerated right after harvest, unwashed and loosely packed.

Broccoli, cabbage and cauliflower last 3 to 6 days in the refrigerator, and bell peppers last up to 5 days in a mesh bag. Any cut or prepared produce should be refrigerated and used within a few days.

The guide’s final rule applies to all of it. Produce that shows mold, discoloration, a foul odor or a major change in texture should be thrown out rather than eaten.

This article was produced with AI assistance and edited for accuracy against the sources linked above.

Image: USDAgov – Public domain/Wikimedia Commons