Peonies come back year after year, with a root base that grows wider as time goes by, resulting in more blooms. As landscaping matures, it may be necessary to move peonies and transplant them somewhere else. Perhaps your shade tree is stealing their sunshine or the root base has outgrown their planter. Either way, peonies should be transplanted with care and an understanding of the peony life cycle for best results.
Cut down the dead peony stalks, cutting close to the ground, in the fall after all of the leaves have died. In much of North America, this should be done in September. This is the only time of year you can safely transplant a peony, so plan ahead. Your new location should be sunny with soil that drains well.
Lay the 3-by-3-foot tarpaulin on the ground next to your peony bush before you start digging. This will give you a safe place to set the root base once it's out of the ground.
Dig out the root base by pressing the shovel into the ground 6 to 8 inches past the outside of the root base. This will protect the outer tubers and make sure that the dirt that's closest to the root base remains undisturbed. You should be digging 8 to 10 inches deep. Most peony varieties will not have roots this deep in the fall.
Lay the root base on the tarp and wrap the tarp around it for safe transport to the new location. Avoid keeping the peony plant out of the ground for long. The sooner you get the plant back into the ground, the better. Do not allow the root base to become too wet or too dry during this time and keep the roots out of direct sunlight.
Dig a hole in the new location where you wish to transplant the peony bush. Mix the soil around the hole with compost and gently lay the root base inside the hole. Sprinkle soil in a little at a time, making sure there are no air pockets, and press down firmly, making sure that the crown is 1 inch or so below the top of the soil.