Judie, I would suggest that you buy some retayne and use that when you wash your big piece. If you can't find that maybe some white vinegar in the wash, and I think I would wash it at least twice, since it is dark colored. If you are washing it in your home washer, you can always check to see if it faded out any in the water. I would wash it in hot water to set the dye, if possible. If you can get retayne, use it. I prewashed some dark colors for a queen size quilt I made my daughter, but I washed them in cold water, and thought they would be o.k. I didn't know about retayne then. Well after the quilt was finished and was washed for the first time some of the dark green faded. I am still working to try and get the excess dye out. It is slowly but surely coming out with some dry powder I bought at Hancock's. Goog luck. Gerbie