if it's 5 you could try digging it up & dividing it this fall. you should be able to get a couple of extra roots from it. of course peonies don't like being moved but they will recover if done in the fall. I moved some of mine from the back yard to the front yard a couple of years ago & they are all ready to bloom anytime now. it's worth a try.

Molly is one that doesn't tend to grow very quickly and I'm not sure about the roots, if they're as tough as most herbaceous or more fragile like fernleafs. Regardless, you'd need to divide it in the fall after it starts dying back. Hopefully someone who has one big enough to have divided before will give you more specific advice!

Thank you all! I'll give it a try in the Fall.