Tree peonies (Paeonia suffruticosa) are considered the national flower of China and can reach heights of nearly 6 feet. A woody or deciduous shrub, tree peonies come in a variety of colors and do well in USDA zones 4 to 9. Typically, tree peonies can live for more than 100 years and do not like to be transplanted. However, with careful attention to detail, you can successfully transplant them. It is best to move a tree peony only in the fall and you can expect the tree to take two to three years to stabilize to its normal, healthy state.
Choose a location where your tree has at least 3 to 5 feet of room to grow into. It should also receive at least four to five hours of sunlight daily, adequate drainage and good soil. Test the soil's pH level. Ideally, the soil should have a pH level of 6.5 to 7.0. If your soil is has a pH of less than 6.5, add lime and compost until you get the right pH. If your soil pH is higher the recommended levels, lower it by introducing an elemental sulfur material using 6 to10 lbs. per 1,000 square feet. Repeat until you achieve a pH between 6.5 and 7.0.
Dig around the tree with a large garden fork at least 18 inches away from the tree trunk. Carefully lift the peony tree out of the earth with a shovel and wrap the root system with a tarp or place the tree in a large bucket while you are moving it to its new location. This can be a slow process because peony roots are tough.
Dig a hole large enough to encompass the entire root system in width and depth. Bury the tree until the soil reaches just below the crown of the tree. The crown of a tree is where the trunk and main branches begin. Depending on the size of your tree, 2 inches above the root system is a good rule of thumb.
Add soil and water to fill in the hole around the tree's root system. Adding the water will get rid of air pockets that will damage the roots if left behind. After your tree is successfully planted, add a slow-release, low-nitrogen fertilizer following the manufacturer's instructions.