Prevent mildew on clothes by storing them correctly. Always be sure they are 100% dry before storing. Avoid storing in plastic bags or boxes, which can trap moisture. Ventilate storage areas when the weather is good or the opportunity presents. Pack storage areas loosely allowing air to circulate. Don’t use starch or fabric softener on items to be stored. Use a chemical desiccant (absorbs humidity) like packaged silica gel to absorb humidity.