Can peony leaves and stalks be composted? Can rhubarb leaves be composted? If not, why?
Peony foliage should not be added to the compost pile because botrytis blight (also called gray mold), a fungal disease that affects peonies. Rhubarb leaves, on the other hand, may be added to your compost pile. While the leaves contain oxalic acid, this rapidly decomposes in the compost pile.