“Keep an apple with your potatoes.” My grandmother said this to me while I was helping her unpack groceries, and I fully assumed it was one of those old wives’ tales that do not hold up. She had plenty of those — putting butter on burns, gargling salt water for everything. But this one? It is backed by actual science.

Potatoes sprout because of ethylene gas — a naturally occurring plant hormone that triggers the sprouting process. Here is the twist: apples also release ethylene gas as they ripen. But when you put an apple in with your potatoes, something counterintuitive happens. The ethylene from the apple actually suppresses sprouting in the potatoes rather than accelerating it.

How to Do It

It could not be simpler:

1. Store your potatoes in a cool, dark, well-ventilated spot — not the fridge (cold converts potato starch to sugar and ruins the texture).
2. Tuck one apple into the bag or basket with them.
3. Replace the apple every two to three weeks, or whenever it starts to go soft.

I keep my potatoes in a paper bag in the pantry with a single apple. Before I started doing this, I would find sprouts within ten days. Now my potatoes last three to four weeks with barely a bump on them.

A Few Extra Things That Matter

The apple trick does most of the work, but these help too:

• Keep potatoes away from onions. Onions release moisture and a different gas that speeds up potato spoilage. They are terrible roommates for each other.
• Do not wash potatoes before storing. Moisture invites rot. Wash them right before you cook them.
• Remove any potato that is already sprouting or soft. One bad potato will spoil the whole bunch faster.
• Darkness matters. Light triggers solanine production, which turns potatoes green and makes them bitter and potentially toxic in large amounts.

Does Any Apple Work?

Yes. Red, green, whatever is in your fruit bowl. I use whatever apple variety is cheapest that week. The ethylene release is similar across varieties — a Granny Smith works just as well as a Honeycrisp.

My grandmother passed away a few years ago, but every time I toss an apple into the potato bag, I think of her kitchen. She was right about this one. (She was wrong about the butter on burns though — please do not do that.)