The deciduous tree peony (Paeonia suffruticosa) grows as a woody shrub that attains a height of 3 to 5 feet with a 4-foot spread. A few cultivars have been known to attain heights of 6 to 10 feet. Flowers often measure 8 inches across in shades of pink, yellow, purple, white and red. Once planted, the tree peony is difficult to transplant due to its deep root system. The tree peony grows well in USDA zones 4 to 8, according to the Missouri Botanical Garden. Plant the tree peony in the fall at least six weeks prior to the first hard freeze.
Plant the tree peony in full sunlight for the best blossom production. The plant will grow in partial shade, but it will produce less flowers. In windy regions, choose a location that offers wind protection.
Add aged manure and peat moss to the planting location. The tree peony thrives in full, well-draining soil with ample organic matter. The soil should feel crumbly to the touch.
Plant the tree peony with the bud graft at least 6 inches below the soil's surface. Dig the hole twice as large as the shrub's root system. Tamp the soil down to remove all air pockets.
Apply 3 to 4 inches of mulch around the tree peony. Water the shrub thoroughly once planted.
Fertilize the tree peony in the spring following the fall planting, again after the tree peony begins to flower, and one more in the fall. Use a general purpose fertilizer such as a granulated 10-10-10 fertilizer. Follow the directions on the label for application.
Remove only the dead or damaged winter wood of the peony tree in the spring. Prune away any sucker growth during the summer months. Remove dead flower-heads after flowering ceases.