The peony has been a popular perennial in American gardens since the 1800's. The peony is hardy, dependable, long-lived, and easy to grow. Gardeners value the peony for its large, colorful flowers in spring and attractive, season-long foliage.
Peonies can be left undisturbed in the garden for many years. Occasionally, however, it becomes necessary to move established plants. Peonies shaded by large trees or shrubs bloom poorly and should be moved to a sunny site. The redesign of a perennial bed or border may require moving the peonies. Large, old plants may become overcrowded and flower poorly. Large, poorly blooming peonies should be dug, divided, and transplanted to improve performance.
Moving established plants is a simple procedure. Cut the peony stems near ground level in September. Then carefully dig around and under each plant. Try to retain as much of the root system as possible. Promptly replant the peony in a sunny, well-drained site.
Division of large peony clumps requires a few additional steps. After digging up the plant, gently shake the clump to remove loose soil from the root system. Using a sharp knife, divide the clump into sections. Each section should have at least 3 to 5 buds (eyes) and a good portion of the root system.
Peonies perform best in full sun and well-drained soils. When selecting a planting site, choose an area that receives full sun. Avoid shady areas near large trees and shrubs. Poorly drained soils can often be improved by working in large amounts of compost or peat.
When planting peonies, dig a hole large enough for the entire root system. Place the peony plant in the hole so the buds are 1 to 2 inches below the soil surface. (Peonies often fail to bloom satisfactorily if the buds are more than 2 inches deep.) Fill the hole with soil, firming the soil around the plant as you backfill. Then water thoroughly.
In late fall (November), apply a 2 to 4 inch layer of mulch over the newly planted peonies. Straw is an excellent mulch. Mulching will prevent repeated freezing and thawing of the soil during the winter months that could damage the plants. Remove the mulch in early spring before growth begins.
Transplanted peonies will not bloom well the first spring. In fact, it's advisable to remove any flower buds that form the first year to maximize plant growth. Transplanted peonies should bloom well by the third or fourth year.
This article originally appeared in the August 27, 1999 issue, p. 116.