So we did a little digging.
First, dirty wet sponges are the worst offenders. Rinsing and wringing out your sponge after every use will help keep bacteria to a minimum, as they thrive in moist environments. Prevention here is key, so make sure your sponge is stored somewhere where air can circulate around it – a soap rack is perfect for this! Sunny spots are a bonus given the sun’s natural bleaching power.
Alas, what to do when that smell has already arrived. We tried a few of the most common tips out there, and here were our results.
Vinegar: Add the sponge to ¾ cup of distilled white vinegar, and let it sit anywhere from 10min to overnight. Rinse it out, and the smell and germs are gone.
Bleach: Make a solution of 5% bleach in water, or 2tbsp in 2 cups of water. Soak the sponge at least 5 minutes. Rinse thoroughly.
Microwave: Start by fully hydrating your sponge (dry sponge + microwave = no bueno) and then put it in the microwave for 2-4 minutes. Be careful here, the sponge will be very hot, so use caution removing it from the microwave! The bacteria-killing properties of this method were tested and confirmed by the Journal of Environmental Health
Dishwasher: Great option works but sometimes this means you need to keep an extra sponge around if your dishwasher cycle is long or if you only run it every few days.
Choose the method that’s right for you, and clean your sponge every week or so, replacing it every 3-4 weeks as needed!