How are you dealing with skirt/dress gems that roll up?

I haven't found a way to deal with rolled skirt/dress hems that I'm happy with. How are you dealing with the issue? Have any of you found a way to prevent it?

Last fall I decided to try using pants hangers on my dresses with hems that roll. I fold the skirt into thirds or quarters, make sure the entire hem is flat, and then secure the flat hanger bar across the hem.

But when I took the dresses down after hanging that way for 6 months, the hem rolled back up!

Plus these suckers are so hard to iron flat!

Edit: spelling