You might want to make your outdoor wall hanging will outdoor fabrics instead of cottons. I made my porch furniture cushions using outdoor fabrics in bright colors and they have not faded yet and they're on the east side too. The cushions I made using oil cloth did fade though and they were on the west side of the house. Only problem with outdoor fabrics is that you can't wash them so I just sweep them off as best I can before I put them into storage for the winter each year. Its been 2 years now since I made them.