Tree peonies begin to bloom before the garden peonies in April to May with flowers that can be 6-8 inches across. (Photo by Ginny Rosenkranz)

Tree peonies or Paeonia suffruticosa are a close relative of the herbaceous or garden peony, but are considered shrubs because the stems do not die back in the winter.
They can grow 3-5 feet tall and 3-4 feet wide in full sun to part afternoon shade and moist, well-drained rich soils.
These lovely shrubs are grafted, and only need pruning to cut out dead branches or any suckers that are coming up from the roots.
The tree peonies begin to bloom before the garden peonies in April to May with large flowers that can grow up to 6-8 inches across!
The species tree peony come in colors like pink to white with some having petals sporting a purple basal patch and are very fragrant. The cultivars increase the colors of the flowers to include red, pink, purple, white, yellow, copper and coral.
The flower forms can be singles with petals on the outside of a center like “Sea of Tranquility,” or have a center bouquet of petals surrounded by flat petals on the outside. Some flowers that have almost more petals than can be counted like “Souvenir de Maxime Cornu.” Because these colorful plants are from the orient, many have some delightful names like “Dragon Coiled in the Mist Grasping a Purple Pearl” or “White Screen Reflects a Blue Jewel,” while others include their color in their name like “Copper King” or “Coral Star.”
Plants should be planted in the fall to allow the roots to get established, and then watered 2 to 3 times each week the first summer to encourage the plants to thrive in their new locations.
These beautiful flowering plants can be planted as a colorful border or hedge or as a jewel in the garden as a specimen.
Hybrid peonies are a cross between the tree peony and a garden peony. These were started by a gentleman named Toihi Itoh in 1948. These beautiful plants combine the large colorful and showy flowers of the tree peonies with the growth habit of the garden peony, and they bloom between when the tree peony blooms and garden peony bloom.
Peony ‘Bartzella’ has become one of the most famous of the Itoh peonies. The Bright yellow semi to fully double flowers is highlighted with crimson red in each center and expand up to 6-8 inches across. Not only are these lovely flowers impressively beautiful but they also have a light sweet citrusy fragrance which attract colorful butterflies.
Young plants will present 30 flowers the first year while a mature plant can present over 60 flowers in spring.
Flowering can last up to three to four weeks with the center flowers blooming first and the side flowers continuing with the color and fragrance. These beautiful flowers are also excellent as cut flowers and will last at least a week in a vase. The deep green glossy foliage comes up from the ground in early spring to spread 2-3 feet tall and wide.
These beautiful flowering plants can be planted in groups, in a border or as a single spectacular plant that neither deer or bunnies will nibble on.
(Editor’s Note: Ginny Rosenkranz is a commercial horticulture specialist with the University of Maryland Extension.)