How to Divide a Peony

Peonies grow best in USDA zones 5 to 9.

Peonies grow in a range of sizes and colors, with a wide variety of flower shapes and petal counts. These bushes require some precise growing conditions, including relatively cool weather, partial sun, loose soil and adequate space. Peonies stop growing and blooming when they become crowded, and require occasional division for continued growth. Divide your peonies carefully and at the right time to avoid stressing the plants.

Things You'll Need

• Organic compost
• Garden fork
• Pruning shears
• Shovel
• Knife/clippers
• Mulch

Instructions

1. Divide peonies in fall, after they go dormant. Dormant pruning and dividing reduces plant stress and healing time. Divide peonies every 10 to 12 years to keep them healthy.

2. Prepare the new planting site before you start, to keep the process quick. Plant the new peonies in sites with partial to full sun and quick drainage. Peonies do best with six hours of bright sun every day, 4 to 5 feet of growing space and rich, quick-draining soil. Dig into the top 8 to 10 inches of soil in each site, in a 2-foot-wide section, and add 4 to 5 inches of organic compost.

3. Trim the established peony to within 3 inches of the ground. This standard fall peony pruning keeps the shrubs healthy through winter and makes the division and transplant process easier.

4. Dig the peony up at the roots and lift it out of the soil. Brush soil from the root ball and look for natural divisions. Cut each division to have three to five eyes, or growing nodes, and a portion of the roots. New shoots grow from these nodes, which look like small red noses.

5. Replant the established peony and move the divisions to the new sites. Dig holes slightly deeper than the new root systems and twice as wide, and spread the roots in the new holes. Keep the buds on the new divisions 1 to 2 inches below the soil surface to keep them from drying.

6. Pack amended soil firmly around the new root systems to secure them, and water each with 1/2 gallon of water. Cover each planting site with 2 to 3 inches of organic mulch to protect the peonies through the winter.

References

• University of Illinois Extension; Time to Divide Peonies?; Sandra Mason; August 2005
• "Horticulture & Home Pest News"; Transplanting and Dividing Peonies; Richard Jauron; August 1993
• North Carolina State University; Peonies for the Home Landscape; Erv Evans; February 1999
• La Pivoinerie d'Aoust Peony Nursery: How to Grow Peonies