This is exactly one of the primary reasons I treat my quilting fabric with a product that I have previously used to set the dye in the fabric I buy for quilts. The Number One reason I wash all my fabric is the chemical residues which remain in the fabric -- I am asthmatic, and I won't risk having the unwashed fabrics in my house. I always test every fabric I'm using in a quilt by cutting a strip about a half-inch wide and 6 inches long, and immersing the strip in a glass of the hottest tap water available. I leave the strip in the glass of hot water for about an hour, then dip a solid white paper towel in the water. The white paper towel will reveal whether the fabric is a bleeder. If it is, then I use Ritz Laundry Treatment Dye Setter to permanently set the dye in the fabric. I have used this product quite a few times and I've never had a treated fabric bleed. I have no financial or other interest in the Ritz product -- it's just that I have used it for several years and have found it to work every time. Today's fabrics are dyed chemically, not organically, and most of the old-time home remedies just won't work on them. The red and white log cabin quilt (my avatar) is an example of how this product works. Every one of the red fabrics were tested, treated and did not bleed thereafter. Discretion is the better part of valor -- I always wash my quilts using color-catchers!