Leafy greens are a staple of any well-stocked refrigerator, but they’re also prone to turning into a slimy, brown mess with alarming speed. People who wrap them tightly in their original store packaging or use a sealed plastic container may still find their iceberg or romaine leaves wilt easily, with their lettuce wraps or salads turning into a sad spectacle.

Fortunately, there’s a way to extend your lettuce's life—and it won’t cost you anything.

The best way to store lettuce in your fridge is to use a few damp—not wet—paper towels as an insert, lining the container at the bottom and putting the greens on top.

This may seem counterintuitive, as wilting lettuce seems to be damp, and you’d think fresh lettuce would require dry conditions to stay crisp. But lettuce needs both air circulation and moisture. The damp towels prevent the lettuce from drying out, while airflow keeps it crunchy. (Oxidation can turn lettuce brown, but as long as you’re consuming it within a few days, it won’t matter.)

For whole heads, it’s a good idea to chop them up, wash them, then spin them dry in a salad spinner if you have one. (A rinse not only gets the leaves damp, it also gets rid of any lingering bacteria. You can also soak the leaves in a bowl so the grit falls to the bottom.) With the lettuce still slightly wet, grab the damp paper towels and put them in a bowl or other container that provides airflow. If it’s bagged, do the same thing—you want it out of the plastic so that air can circulate. If you keep replacing the damp towels, your lettuce should stay nice and green for three to five days.

[h/t The Spruce Eats]