rolling hem fix

Several of my ready-made garments have rolling or curling hems. Does anyone know of a fix for this problem?

the problem is that the hem is not stitched with the grain of the fabric - you get this issue on curves and bias cut garments almost without fail, and with many fabrics that have a stretch.  The dryer often shrinks the thread at a different rate than the fabric, hence runching seams and rolling hems.  You have a couple of solutions that I can think of -
1 - hang to dry or dry them flat, then touch up iron as needed.

2- rip out the hems and re-hem using bias tape.  to do this, rip out or cut off the old hem, pin the bias tape to the raw edge and press it, stretching or scrunching a bit as needed to make the curves, then stitch the bias tape to the raw edge, then turn up, press into place and stitch down - you may have to hand sew it, and you may still want to dry it flat or hang it.  The only way to get a hem on a curve to guaranteed lay flat is to cut an identical curve facing. 

hope this helps!
Sarah