Way more often than you're doing it
As a person who both cooks a lot and doesn't have a dishwasher, I end up using my fair share of kitchen sponges. Those cheerful bright yellow and green numbers get through a sink full of dishes without number, but there comes a time in every sponge's life when things begin to go downhill. When should you throw out your kitchen sponge? I'm always hesitant about swapping out a sponge too soon, because it feels like a waste of money, but nor do I want to just be swiping around bacteria and dirt all over my dishes when I think I'm cleaning them. How can you tell when a sponge is all sponged out?
The information out there on sponge replacement, um, wasn't comforting to me. Obviously this is a matter, somewhat, of preference, and of how often and how seriously you use your kitchen sponge. But, as Philip Tierno Jr, a professor of microbiology at the NYU School of Medicine, told Self on the subject, "The kitchen is a germy place, and the germiest item in it is a sponge." Makes sense really—it's a moist, porous environment, and therefore a friendly environment to all kinds of unfun bacteria. You're actually much more likely to contract food poisoning from your own kitchen than from a restaurant, and your sponge might be a culprit. Fun! But Teirno doesn't recommending throwing out your kitchen sponge after every usage, but sanitizing it way more often instead. To sanitize a sponge, you can either submerge it in a mixture of nine parts water to one part bleach, or zap it in the microwave in a bowl of water for about a minute. And here's the thing: You should be sanitizing your sponge pretty much every day to avoid unfun gastrointestinal distress.
If you're sanitizing your sponge, it can last quite a while. But if you, like me, didn't really know that you had to do that, how often should you change your kitchen sponge? The CDC recommends changing your sponge every two weeks. In fact, some experts recommend you change your sponge out once a week. Yes, really. Yes, that's a lot. Yes, I'm going home now to throw away all my sponges. Food poisoning is just not worth it.