Fresh cucumbers last for about one week in the fridge, which is a far shorter shelf life than that of heartier vegetables like carrots, which can last for a month. After one week passes, you might slice your cucumber open, only to find that it has developed a bizarre coat of slime, a byproduct of the cucumbers' high moisture content.

Cucumbers are 96% water, and the high-moisture environment of the fridge can overwhelm the veggies with humidity, which accelerates the rotting process. Cutting into a cucumber and finding slime is a definite signal that it’s past its prime, but you might be tempted to simply wash the slime off and use the cukes.

The hard truth is that you absolutely should not eat or prepare food using slimy cucumbers. Washing the slime off does not stop or reverse the rotting process, which already began far before you noticed the slime, so throw out those slimy cucumbers, next time you buy fresh ones, eat them as soon as you can.