Answer: To be honest, in my experience all peonies will fall over if there is a heavy rain or wind storm when they are in bloom. (And of course this happens almost every year.) So to prevent that you might wish to use some type of supports. The traditional round wire "peony rings" are very unobtrusive if not invisible once the peonies fill them. They are a snap to set out in the spring and remove in the fall and some types even fold flat for storage. A less expensive but more time consuming method is to simply tie several twists of string somewhat loosely around the perimeter of the clump.
For such a beautiful line of plants, I would support them just to be sure. The added bonus of course, is that means you can select the colors and forms you like the most without worrying about stem strength so much!
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