Find out exactly when to cut back peonies and how to do it properly to benefit next year’s blooms. Bob Stefko Herbaceous peonies (Paeonia lactiflora) are among the easiest flowering plants to grow. One key to success is knowing when to cut back peonies and how to properly make your cuts. These perennials produce new growth from the plant's crown in spring, which dies back to the ground after a...