I am pretty strongly in the pre-wash, dye-set mode. My first large quilt (a very large queen-sized, hand embroidered quilt) with bright red borders. Before I cut the first strip of pieces, I sliced off a 1/2" wide by 6 inch long strip of the red and put it into a glass of hot tapwater, stirred it around and you could see the dye had bled into the water. Now, the interior of my quilt was embroidered on white. Had I not determined that I would dye-set the borders, that quilt could have ended up in the trash! I bought a product which I found online from the Rit Dye website, ordered it, it came by Federal Express, and the product is not expensive. I have NO financial interest in the Rit Dye company -- I just use and very much appreciate that company's product. Any color that is a vibrant color (and yes, sometimes, even black) can bleed. The dyes used today are not organic dyes. It's not necessarily that the fabric is fading, but that the dye residue wasn't rinsed out of the fabric. The first thing I do when fabric comes in the door, I will serge the ends of the fabric to prevent a raveling, stringy mess. Then, I process it so I can be very sure the fabric is not going to bleed all over the adjacent fabric!
JMHO!
Jeanette