Keep your pruners sharp if you grow peonies. These perennial favorites require only moderate pruning, but it’s important. Knowing when to cut back peonies is vital to keep diseases at bay, as is deadheading peonies. Not sure when to cut down peonies? Do you deadhead peonies? If you have questions about peony pruning, we have answers.
Both times you prune these perennials—when you’re cutting back peonies and deadheading peonies—you’re tackling simple tasks that don’t require too much expertise. When you’re cutting peonies, like any plant, it’s a good idea to wear gloves to protect your hands. Make sure pruners are sharp and clean before starting any cutting job.
Deadheading peonies is the process of removing spent blooms. When you remove faded flowers, you stop plants from producing seed pods, which allows plants to direct all energy toward food storage in tubers. That stored food supplies the energy needed for next year’s growth and flowering. Faded peony flowers also tend to develop fungal diseases, like botrytis, as petals rot. By removing the blossoms, you can help keep fungal diseases at bay.
When deadheading peonies, some gardeners just snip off the flower head itself, but this leaves a long stem in place that stands taller than the rest. It’s better to follow the flower stem into the plant and place your cut about half an inch above the leaves.
Cutting back peonies is a once-a-year task. When to cut back peonies? The right time for peony pruning is in fall, after frost has killed leaves. How to prune peonies? Clip stems as close to the ground as possible. Gather all leaves, stems and any other plant debris. Don’t compost this leafy material; bag it and put it out with the trash. Destroying it is better because peonies often have fungal diseases that can survive winter on a piece of leaf or stem.
Peony pruning really only comes into play with tree peonies, which have woody stems. With these plants, pruning isn’t usually necessary. The most common pruning you’ll tackle with tree peonies is removing winter-damaged wood in late spring. This occurs most often in colder regions where harsh winters can kill some of the stems. Wait to prune until late spring, when growth has clearly resumed from some of the buds. Place pruning cuts just above an outward-facing bud. Cut stems at an angle.
Some gardeners argue that there’s never an occasion for pruning peonies. They don’t believe in deadheading, saying it makes no difference on plant health. Other gardeners never worry about cutting back peonies in fall and just let leaves deteriorate in the peony patch. Deciding to tackle peony pruning is really a personal choice, but it will always help improve the health of your plants. Removing hiding places for diseases is one of the best ways to keep any plant problem-free.