A peony bush may be any plant in the Paeonia genus, which has 25 to 40 species. These plants have a highly variable appearance, but are well-known for their spectacular blooms in the early summer. Peonies are quite hardy as long as they have good drainage. They are quite sensitive to transplantation, so you'll typically replant peonies by dividing a mature plant.
Transplant mature peonies during the fall. These plants will need a fully developed root system to survive transplantation. Peonies are vulnerable to the summer heat and the stress of blooming. You should only transplant mature peonies after the foliage dies in the fall. The plants will be dormant and therefore much more likely to survive the stress of transplantation.
Prepare the peonies. Water the mature plants thoroughly the night before transplanting them so the water can soak into the soil overnight.
Remove the leaves and dig out the soil away from the plant to get as many roots as possible. Remove the entire plant and wash the root ball. Divide the plant with a sharp knife so that each division receives a minimum of five buds.
Select a site. The new location should provide the peonies with full sun. However, climates with hot summers may require you to use a location with some shade during the afternoon.
Place each division in its new location. Cover the eyes with less than 2 inches of soil. Peonies benefit greatly from division because the divided plants grow much more quickly. Divided peonies may bloom the first year after transplanting, while a whole plant may not bloom for several years.