I used to NOT WASH my fabrics but when I saw the thread on this forum for the poor lady that made the beautiful quilt for her Mom and she washed it and the backing fabric bled all over the quilt and she had washed the fabric prior. I am washing all mine and taking care that it will not bleed. I just washed some black fabric I am going to use in a border of my horse quilt. I used color catchers and they were very gray dark looking so I washed the fabric again and got 3 more very gray looking color catchers. So I washed again and 2 more color catchers and put two or three scraps of the white fabric I used in the quilt. All came out well.....no bleeding on the white fabric. So at least I feel like I know what is going to happen when I do wash my quilt. NOTHING, at least no bleeding...lol.