After retrieving my scraps from constructing the Double Delight quilt, I realized that I did not remember what I planned for the border. So, I had to put everything out on the guest bed and start over.
After pondering the design, I finally came up with this simple solution. I was limited by two things: I had almost used up all of the fabric selections pieced into the center, and while I still had a large piece of green fabric, the quilt contained so much green that using it for the border completely drowned the whole thing. I wanted to bring some of the blue out of the center into the border, and divide it from the green triangles with a narrow yellow strip. There was barely enough of this blue left. Adding a nine patch block at the corners enlivened it. Then, using the remains of one of the brown fabrics for the binding brought out the rest of the block colors to the edge.
I would have liked to add a second 3" strip of blue with another nine patch corner block as Bonnie Hunter did on the Quiltville quilt, but I didn't have enough of any of the blues I used in the blocks. I considered a border of green, but that didn't improve the quilt. At last, I decided to leave it with this narrow border since the center is so busy. It isn't a large quilt, just 72" x 84", but it is for a full size bed, and it will be all right.