Pruning peonies can be a tricky task for many gardening enthusiasts. Whether you’re working with herbaceous, tree-like, or intersectional hybrids, understanding the right method for each type is crucial for maintaining healthy and beautiful plants. In this guide, we will explain how to prune peonies properly, offering expert tips to ensure you make the right cuts at the right time.
Types of Peonies
Peonies come in three main varieties: herbaceous, tree-like (shrub), and intersectional hybrids. These types differ in their growth patterns and pruning requirements, so knowing which type you have will help you make the best decision when it’s time to prune.
Herbaceous Peonies
Herbaceous peonies are the most common type. These plants die back to the ground each winter, and in spring, they sprout new growth from the roots. The pruning process for herbaceous peonies is straightforward. To encourage healthy growth, cut them down to the ground level before new shoots emerge in late winter or early spring. While you can prune them in the fall after the stems dry up, it’s better to wait until spring. Old foliage offers natural protection for new buds, especially in colder climates.
In cases of fungal infections like leaf spots (caused by Septoria paeonia), which can appear in late fall, early pruning helps prevent the spread of spores to the new growth.
Intersectional Hybrids (Itoh Peonies)
Intersectional hybrids, or Itoh peonies, are a cross between herbaceous and tree peonies. These plants have both woody and herbaceous traits. When pruning, cut back the plant almost to the ground, leaving the short, woody stems. These stems may contain buds that will sprout new growth in spring. Like herbaceous peonies, the majority of the new growth will come from the root buds. If part of the old woody stems dies back in the spring, don’t worry—it’s completely normal and won’t harm the plant.
Tree Peonies (Shrub Peonies)
Tree peonies are quite different from herbaceous varieties. Unlike the others, tree peonies have woody stems that remain year-round. Generally, these plants don’t require much pruning. However, there are specific situations where pruning is beneficial.
- Encouraging Branching: If a tree peony has only a couple of bare main branches, pruning can help stimulate new growth. Cutting back the stems encourages the plant to develop more lateral branches.
- Damaged or Broken Stems: Tree peonies have brittle wood, which can break under heavy snow. If the crown of the plant is still intact after a break, you can prune the damaged stems above the break, just above an outward-facing bud. If too many branches break, a heavier pruning may be necessary, cutting the main stems back to about 30 cm above the ground. This may result in no blooms for one season, but the plant will eventually recover and flower again.
Tree peonies, like all woody plants, need to be in good health and well-established before you attempt a hard pruning. They rely on a strong root system to push out new growth after a heavy cut.
Key Pruning Tips
- Time Your Pruning Right: For all peony types, the best time for pruning is during late winter or early spring, just before new growth begins. For tree peonies, only prune damaged or dead stems, as excessive cutting can damage the plant.
- Remove Dead Flowers: For all types of peonies, removing faded flowers helps prevent seed production and encourages better energy flow to the roots and remaining buds.
- Be Mindful of Disease: Keep an eye out for fungal diseases and prune affected areas early in the season to prevent spread.
By following these guidelines, you’ll ensure your peonies thrive and bloom beautifully year after year. Each variety has its own specific needs, but with the right approach, all types can be a stunning addition to your garden.