I have a outdoor swing that had very dirty & mildewed cushions. I was about to give up an find some new ones but the cost got the better of me. I spread them out on my deck, sprayed them with bleach and some soap and took a broom and started scrubbing. I was amazed at how cleaned they looked after they dried. Its worth the effort, if your afraid to use bleach try a non-chlorine type cleaner, or get some "greased lightening" and get scrubbing. Make sure you rinse the cushions out well and hang over something to dry. Good luck!