To save limp lettuce or herbs, all you have to do is fill a large bowl or clean sink with ice water and soak your lettuce until it looks crisp and alive again, about 20 to 30 minutes. You can use this trick to save almost any leafy vegetable or herb, like parsley, cilantro, lettuce and kale. Test Kitchen Tip: To prevent your lettuce from going limp in the first place, be sure to store it in a bag in your crisper. Also, follow these instructions to wash and store lettuce and herbs to ensure that you prolong the life of your lettuce.