|This time of year (summer) I make a lot of kids tops from print remnants, as they don't take much fabric - halters, sleeveless, etc. And I use leftover solids to make shorts. To tie them together as a set, like RTW and also to stretch the fabric (because I can skimp on the length of the hem this way), I cut strips, 1 1/2 to 2" of the print and join them into one long strip to bind the shorts hem. I sew the right side of strip to wrong side of shorts leg, press the binding strip up over the bottom raw edge toward the right side, then I press the rest up to the right side and stitch the top edge.
What you are doing is encasing the bottom hem fabric in a binding strip and sewing it toward the front. This ties the printed top and shorts together very nicely, gives a neat and very RTW finish, and stretches the fabric. No hand hemming or fusing, all done by machine.
If you don't have enough print for the strips, or you're just making shorts, use purchased binding and add a touch of color or contrast. You can cut the shorts to the length of the hemline, rather than adding the 2" or whatever the hem allowance is.