Table Runner Quilting Spacing
On a 14 1/2" x 73" quilt-as-you-go table runner made of 21 strips (4 blocks per strip), with each completed strip 3 1/2" x 14 1/2", should I stitch in the ditch between the blocks the entire 73" length of the runner to prevent the batting from bunching when laundered?
The quilt shop instructions were that it is not necessary to quilt closer than 8" but my strips are 14 1/2" x 3 1/2".
The blocks are pre-cut cotton, thread and backing are 100% cotton, and the batting is 80/20 cotton poly with scrim. Since the blocks were pre-cut, I did not pre-wash the blocks, backing, or batting.
Also, how should the completed runner be laundered?