Every fall it’s the same story. You buy a big bag of potatoes, or bring in the last of the garden harvest, and three weeks later half of them have pale little shoots growing out of the eyes and have gone soft to the touch. Grandmothers who stored potatoes through entire winters never seemed to have this problem. Their method wasn’t magic. It came down to a few rules about where potatoes live, and one old trick involving a piece of fruit that has more science behind it than it seems.
A potato is a living thing. Stored in the wrong conditions, it does exactly what it’s built to do: it wakes up and starts to grow.
Why potatoes sprout
Sprouting is triggered by warmth and light. In a warm kitchen, near the stove or on a sunny counter, a potato reads the signal that spring has come and starts sending out shoots. Light also turns the skin green, a sign of solanine, a natural compound that tastes bitter and can cause stomach upset in larger amounts. Green patches and sprouts should always be cut away generously before cooking; a potato that’s heavily green or shriveled belongs in the compost.
Grandma’s rules for storing them
The old approach is still the best one:
- Keep them cool: ideally around 45 to 50°F. A cool pantry, basement, garage that doesn’t freeze or unheated closet works well.
- Keep them dark: a paper bag, a cardboard box or a basket with a cloth over it.
- Let them breathe: never store them sealed in plastic, which traps moisture and invites rot.
- Don’t wash them before storing: dirt protects the skin; moisture speeds decay.
- Keep them away from onions: stored side by side, the two speed each other’s spoiling.
The apple in the bag
The famous grandmother’s trick is to tuck an apple in with the potatoes. It sounds like folklore, but there’s a logic behind it: apples give off ethylene, a natural plant gas, and continuous exposure to ethylene is actually used commercially in some countries to hold back sprouting in stored potatoes. One apple in a bag won’t match an industrial store, and results at home vary, but it’s cheap, harmless and worth trying. Replace the apple when it starts to wrinkle.
What about the fridge?
Here the advice has shifted. For years, the rule was never to refrigerate raw potatoes, because cold turns some of their starch into sugar, which changes the taste and makes them brown faster when fried. In 2023, the U.K.’s Food Standards Agency updated its guidance to say the fridge is fine. Many U.S. guides still prefer a cool, dark pantry for the best flavor. If your kitchen is warm and you have no cool spot, the fridge beats a sprouting potato.
Cool, dark, dry, away from the onions, with an apple for company. That’s what kept a cellar full of potatoes firm until spring. That’s the trick.
