Bath pillows are used in a room that happens to be the ideal breeding ground for mold and mildew. If you simply toss your bath pillow on the floor, in the tub, or in a cabinet after using it, there’s a good chance there will be some type of fungal growth. To prevent this, keep your bathroom as ventilated as possible with an exhaust fan, an open window, or both. Then, take the time to rinse off and dry your bath pillow. If that’s not doing the trick, spray your bath pillow with a solution of either water and white vinegar or water and one teaspoon of tea tree oil—both of which should help stop mold and mildew from forming and growing.