How to Store Potatoes So They Stay Firm for Months

You buy a 2.5 kilo bag of potatoes, use a third of it, and two weeks later the rest are soft, sprouting or turning green at the edges. Knowing how to store potatoes properly is the difference between a bag that lasts ten days and one that lasts two months.

The good news is that potatoes are forgiving once you give them three things: darkness, cool air and a little ventilation. Here is exactly how to set that up in a normal kitchen, what to do with sprouts and green patches, and why one piece of advice you have probably heard is now out of date.

How to store potatoes for the longest shelf life

Potatoes are living tubers. After harvest they keep breathing and slowly using up their own stored energy. Warmth speeds that up, light turns them green, and trapped moisture makes them rot. Your job is to slow everything down.

• Temperature: 7 to 10 degrees Celsius is ideal. A cool pantry, an unheated utility room or a garage that stays above freezing all work well.
• Darkness: Complete darkness if you can manage it. Even a kitchen light left on in the evenings will start greening potatoes in a clear bag within a week.
• Air: Use a paper sack, a cardboard box with a few holes, a hessian bag or a basket with a cloth over it. Avoid sealed plastic, which traps humidity and encourages mould.
• Space: Keep them in one or two layers if possible, so one rotten potato does not spread to the whole pile.

Do not wash potatoes before storing them. The thin layer of soil actually protects the skin, and damp potatoes rot far faster. Wash them just before you cook.

Sort them first

When you get home, tip the bag out and check each potato. Remove any that are cut, bruised or soft, and use those within a few days. A single damaged potato can release moisture and bacteria that ruin the ones around it. This five minute job adds weeks to the rest of the bag.

How long different potatoes last

Not all potatoes keep equally. Thin skinned new potatoes are harvested young and have not built up the tougher skin that protects maincrop varieties.

Sweet potatoes are a different plant altogether and dislike cold. Keep them in a cupboard at room temperature rather than the fridge, where they develop a hard core and an off flavour.

The fridge question, and why the old rule changed

For years the standard advice was "never put raw potatoes in the fridge." The reason given was that cold turns potato starch into sugar, and that those sugars form acrylamide, a compound linked to cancer in animal studies, when the potatoes are fried, roasted or baked at high heat.

That advice has been revised. In 2023, the UK Food Standards Agency updated its guidance after new research found that fridge storage did not meaningfully raise acrylamide levels compared with storage in a cool cupboard. The agency now says raw potatoes can be kept in the fridge.

I think this is worth knowing because most modern homes do not have a cool larder. A centrally heated kitchen at 20 degrees is far worse for potatoes than a fridge. In a warm flat, the salad drawer will keep a bag in good condition for around a month, which is often longer than a cupboard next to the oven.

There is still a trade off. Fridge cold potatoes can taste slightly sweeter and may brown faster when fried. If you mostly make chips or roasties, a cool cupboard is still the better choice if you have one. If you mostly boil and mash, the fridge is fine.

Sprouts, green patches and soft spots

Most stored potatoes eventually show a sign of age. Here is how to decide what to keep.

1. Small sprouts: If the potato is still firm, snap or cut the sprouts off and cut out the eye beneath them. The rest is fine to eat.
2. Long sprouts and wrinkled skin: The potato has used up much of its starch. It will be safe once the sprouts are removed, but the texture will be spongy. Use it in soup or mash, or plant it in the garden.
3. Green patches: Green skin is chlorophyll, but it signals that solanine, a natural toxin, is building up alongside it. Peel away green areas thickly. If more than about a quarter of the potato is green, or it tastes bitter after cooking, throw it out.
4. Soft, wet or smelly potatoes: Throw them away and check the neighbours. Rot spreads quickly.

Common storage myths worth ignoring

You will often read that potatoes and onions should never be stored together. The usual explanation is that onions give off ethylene gas, which makes potatoes sprout. In practice, onions release very little ethylene. The bigger issue is moisture, because onions prefer drier air than potatoes. Storing them in separate bags on the same shelf is perfectly fine.

Apples and bananas are the real problem. Both release plenty of ethylene, and a fruit bowl next to the potato basket will push them to sprout within days. Keep fruit on a different shelf or in a different room.

The other myth is that potatoes freeze well raw. They do not. Raw potato turns watery and grey after thawing. If you have too many, peel and cut them, blanch them in boiling water for 3 to 5 minutes, cool them quickly, then freeze in bags for up to 10 months. Mashed potato also freezes well for about 3 months. The same reasoning applies to other staples covered in our guide on how to store bread so it stays fresh: freeze in portions you will actually use.

Storing cooked potatoes safely

Leftover boiled, roast or mashed potatoes should go into the fridge within 2 hours of cooking, in a covered container. Use them within 3 to 4 days. This is the same window as most cooked starches, and it follows similar logic to how long cooked rice lasts in the fridge.

One specific risk is foil wrapped baked potatoes left at room temperature. The foil keeps out oxygen and can allow Clostridium botulinum spores to grow. Unwrap baked potatoes before they cool, and refrigerate them uncovered for the first hour so they chill quickly.

Frequently asked questions

Is it better to store potatoes in the fridge or the cupboard?

A cool, dark cupboard around 7 to 10 degrees is ideal, especially for potatoes you plan to roast or fry. If your kitchen is warm, the fridge is now considered safe and will usually keep potatoes longer than a heated room. The UK Food Standards Agency updated its advice on this in 2023.

Can you eat potatoes that have sprouted?

Yes, as long as the potato is still firm. Remove the sprouts and dig out the eyes they grew from before cooking. If the potato is shrivelled, soft or green over a large area, it is better to throw it away.

How do you keep potatoes from sprouting?

Keep them cool, dark and away from apples and bananas, which release ethylene. Store them in a paper or hessian bag rather than plastic, and do not wash them before storing. Checking the bag once a week and removing any soft potatoes also slows sprouting in the rest.