There is always the debate as to whether to wash or not to wash before you start a quilt. I was not a pre-washer, however a friend of mine who hand appliques everything had to try to wash out a quilt of hers where a purple/green batik ran. The purple in the batik ran & she worked several days to get it out. Still has some spots but only if you look hard. I have washed every batik I bring into the house now for over a year and even though I was told by a LQS that they boil the fabric to get all of the wax out I still have had color run.
So, yes, I always wash and dry my batiks in the hottest water I can use just to be safe.
Happy Quilting,
Susan