My peony 'Raspberry Sundae' collapsed last night. It's been in the ground 10 or 11 years, and although we're in a severe drought none of the other plants within 6 feet of it are suffering, including Peony 'Sword Dance', Achillea 'Summer wine', Calamints, Malva alcea fastigiata, daylilies. No sign of botrytis either in the peony.
There may be some vole activity in the area, but if so, it's nothing like the infestation I had last winter in the same bed, and the peonies were untouched through that.
So, what diseases are peonies subject to, and what might have caused the collapse?
Thanks for your help.