I have had peonies at various houses for years and never had a problem with them. I have been in this house two years and am mystified by what happened to two peony plants in one area of the yard. About mid July after the plants were finished blooming the stems of first one plant then the one next to it started breaking off in the middle of the stem. Later some stems broke off at the base. They sort of split and fell over. At first I thought a critter had chewed on the stem and caused the damage but I'm certain now that's not the problem. I cut open several stems thinking I could find some sort of larva or worm that had done the damage but found nothing. Plants in the front yard well away from the plants with this problem are fine and show no signs of trouble. Any idea what the heck is going on? I should note that the first plant to show problems was purchased and planted this spring. Could I have brought something in on that plant? Hopefully they will come back next year but I'm concerned about their future.