I don't wash precuts -too difficult and not recommended by the manufacturers. For this quilt, though, I will be cutting yardage -four different Star Wars fabrics- plus Kona Cotton Solid Steel Gray, which will make up the backing, binding, and sashing. Because of the richness of the colors in the Star Wars fabrics, I've decided to go ahead, per another poster's advice, and use my regular fabric detergent. Thank you for your advice!