Peony Foliage

Question

My front garden peonies have a thin film of ‘white wash’ look on them this summer; yet, the back garden peony clumps do not. Have lived in house for 15 years and this is first time seeing this.

Answer 1

This is powdery mildew. This article will help with that:
https://www.gardeningknowhow.com/plant-problems/disease/powdery-mildew-homemade-and-organic-remedies.htm