Small brown spots usually aren’t harmful if you eat them. You can also cut around them if the rest of the lettuce leaf is still healthy.

The smell will be so off-putting that you won’t want to eat the lettuce anyway, but it is often accompanied by discoloration and slime on the leaves.

Lettuce wilts right before it begins to turn brown. You will have to discard it or find a use for it right away. Wilted lettuce is safe to eat if it hasn’t begun rotting. You can try soaking it in ice water for up to 30 minutes, which may restore its crispness. [4] X Research source

Although wet leaves may still be safe to eat, they won’t taste very good. The leaves become soft as they wilt.

Moisture creates the perfect growing spot for bacteria and mold, so don’t eat the lettuce. You may be able to see brown spots in a spoiled bag of lettuce. You can also try opening the bag. The lettuce will have that nasty, rotten smell if it has gone bad.

Avoid eating the lettuce if it is sour. Throw it away immediately.

A vegetable crisper is a great place to store heads of lettuce, but not all refrigerators have this drawer. You can also wrap the lettuce in paper towels to absorb damaging moisture. Keep lettuce away from ethylene-producing fruit such as bananas and tomatoes.

Seal the storage container when you are done. This will help keep out harmful moisture and gas. However, unsealed lettuce will still survive well in a crisper. You may want to do this for pre-cut lettuce in a bag as well. Moisture can’t escape the closed bag, so the lettuce may rot faster than you would like.

Be careful when storing lettuce in the back of the refrigerator. Not only does this make forgetting about the lettuce easier, but the cold from the freezer can damage the lettuce. You can also move the container of lettuce to the freezer. Since lettuce has a lot of water in it, it won’t stay crisp, but you can still use it for cooking.

While changing out the paper towels, take the time to pick out any wilted or decaying leaves so they don’t spoil the rest of the batch.

Moisture causes lettuce to soften and decay, so you want to avoid it as much as possible. You may rinse the lettuce off under running water, but lettuce is delicate and may bruise. Bruised or damaged leaves tend to decay faster.

You can also pat the lettuce with a paper towel or roll it up in a towel to gently squeeze out the moisture.