I have some peonies that have more than one flower form on the same plant. Is this diversity the result of genetic instability of the particular cultivars where it is observed, something else or this just how peonies behave, i.e., nothing unusual?

It surprises and puzzles me because flower form seems to be such an important component of a cultivar's descriptuon.

Examples:

Bowl of Beauty, planted spring 2013:







Louis Van Houtte, planted fall, 2012:

I am NOT an expert, but I think this happens until the plant is mature?

Caroline, I think you are correct. Environmental factors can also be a possibility.

Cs, at the APS show today and making particular notes in the field about flower form. There are definitely variations of flower form on some peony plants. And in a row of 50, each plant had some variation of bloom. I didn't notice it on all, but some did for sure. Wonder if some are just that way.

It was an interesting thing to look for today. Thanks for bringing it up here.