I have found a LOT OF RED FABRICS will bleed rivers! Cold water will not "set" the dye. I found a product online, Rit Laundry Treatment a dye fixative) and I swear by it. I ALWAYS CHECK FABRIC, particularly those with vibrant colors. I've even had some deep blues also bleed. I ALWAYS WASH MY FABRIC, and check for bleeding BEFORE I cut out my quilt. Granted, I am a "Rank Amateur", but I found this out, thanks to my cousin who has a quilt shop and carries quilting fabrics. So, if I'm using a red (which I'm making a red and white quilt right now) I automatically treat the fabric with the Rit Dye Fixative product, and, since discretion is the better part of valor, I will also use color catchers when I wash this one (I'm finally doing a quilt for myself).
Jeanette