When can I cut back peony foliage?
Cut back peony foliage after it has been destroyed by a hard freeze. In Iowa, late October or early November is generally a good time to cut back peonies. Cut off the stems near ground level. If the peonies experienced foliar disease problems, remove the plant debris from the area and destroy it.
Plants cut back in August or early September may have fewer blooms that those cut back in fall.