My first thought would be to use a contrasting solid fabric for a backing and applique the hexagon edge onto it. To get the full benefit of the right side of the fabric, one would have to make the backing large enough to fold so the right side shows and will be under the hexagons.
I was asked to finish off a hexagon quilt top this way years ago, at that time, I used a strip of fabric and then sewed the top and backing, right sides together and turned the quilt right side out. I sewed around the outside to secure the backing and top together.
Carol J.