Sometimes when I am using a special fabric on the back, like a flannel with print
that goes with the theme of the front, but it is not wide enough and dont want to pay for another 2 and a half yards, I choose another fabric that blends with that piece, usually a solid, and get just enough to cut it width length, piece it, and sew the strip in between the two pieces of my special backing fabric. It looks planned with a strip down the middle and saves a lot in purchasing fabric.