Instead of using broadcloth, which is a lil tougher to get a needle through that the 100% cotton when doing the actual quilting, I'd purchase the wide, 90-110" backings that are 100% cotton muslin. These backings are located in most fabric shops. I love the wideness due to not having to have seams in the wrong side of a quilt. You can often find a coupon, 50% off that you can use to buy this wide muslin by the yard cut. Just my opinion though - many chose to make the backing with a fabric they've used IN the quilt front - but it is very expensive. The muslin is what the women used in the Olden days!