I have a patio rug that is on a poured patio but no roof over it, it gets alot of weather. Has started to have molded patches on it, and I'm not sure how to clean this? I have plants around the patio area and don't want to use anything that may kill my plants. How do you protect/clean your rugs, or furniture outdoors? I don't seem to have any luck with keeping things nice for long.