No mention of batiks. I prewash those separate because I'm afraid of their dye running. I separate lights and darks to prewash. Just started storing on mag boards and don't iron until use.
Note: I just bought a bunch of pieces of solid fabric (back into applique). Tide pod's colors (bluish and greenish) stained my lavender piece. Washed it again by itself in hot, but no change. Now I will add pods in first, not last, and am searching for new detergent!