I'm a prewasher myself. But that said, I wash all my quilts before gifting just to get rid of dog hair and hand oils, etc. When pre washing fabrics or washing completed quilts I do the same thing. I use the perm. press setting on my washer, warm wash/warm rinse (cause that's as hot as I can get everything). Toss in appropriate amount of regular laundry soap and off we go. Toss in dryer when complete. In your case since the fabrics weren't pre washed, I'd toss in a couple of color catchers since you have them. Check your quilt and the color catchers upon removal from washer. If no bleeding has occurred, toss in the dryer. If bleeding, keep washing till there is none. THEN toss in the dryer. Yes, you'll get some shrinkage - particularly if you used a cotton batt - but I think the batiks tend to not shrink as much as other fabrics due to the generally tighter weave of the fabric.