How to Split a Fern Peony

A peony is any member of the genus Paeonia, which contains 25 to 40 species of flowering perennial plants. The fern peony (Paeonia tenuifolia) is unusually short for this genus and rarely exceeds 1 ½ feet in height. You can propagate fern peonies by splitting a mature plant and transplanting the root divisions.

Difficulty:

Moderately Challenging

Instructions

Things You’ll Need

• Garden trowel
• Compost
• Fertilizer
• Knife
• Mulch

1. Select a site. You need to be in United States Department of Agriculture hardiness zones 3 through 8 to grow fern peonies. They need a winter with a hard freeze to produce their best blooms in the summer. Fern peonies generally do best in full sun but they may benefit from an hour or two of afternoon shade if you’re in an area with a hot summer.
2. Prepare the new site in fall. Loosen the soil to ensure the fern peonies will have good drainage and mix compost into the soil to enrich it. You may also need to add fertilizer if the soil is primarily sandy.
3. Split a mature fern peony in the fall. Water the fern peony the night before you split it and dig it up the following morning. Ensure you get as much of the peony’s extensive root system as possible to provide the divisions with the best chance of survival.
4. Cut the leaves off with a sharp knife and wash the root ball. Split the plant with the knife so each division gets at least five buds.
5. Plant the divisions of the fern peony in the new location. Cover the eyes with no more than two inches of soil.
6. Apply a layer of mulch to the fern peony divisions in the winter and provide granular fertilizer in the early spring before they start to grow.

Tips & Warnings

• Mature fern peonies will normally die back in the fall and you can cut them to the ground once they enter a dormant state, usually after the first freeze.