it depends on the batting!!!
some batts are good for tied quilts and say so on the packaging- some batts HAVE TO BE QUILTED every 2"-4" (very densly) other batts allow up to 10" between stitching lines- those are the ones that work for tied quilts.
when tieing you need to have your ties about every 4"- anyplace you put your fist should touch a tie- top, bottom, side to side (in a grid)