Color matters because dyes can bleed, with red and blue fabric causing the most trouble, according to Mary Zeitler, a consumer scientist at Whirlpool Corporation’s Institute of Home Science. “However, after a few washes, dyes become less likely to release and transfer to other clothing,” she explains.
It’s not just when you wash, but how you wash your clothes also matters to unwanted color crossover. Dyed pants (e.g., jeans) will stay blue (or black) longer when they’re washed inside-out; their outer-dyed surface won’t rub against as many other clothes. And, using cool water in the wash can help cut down on bleeding for all colors.