Ever wondered if it’s okay to wash your down comforter without taking it to the dry cleaners? You’ve wondered correctly! You can absolutely wash your down comforter sans the pros. All you need is a mild detergent, and a few hours spent at the laundromat. And patience. Did I mention patience? Mild or all-natural detergent Tennis balls Extra large capacity front-loading washing machine Extra large capacity dryer or sunny outdoor space 1.