Q. Do tree peonies need special care when grown outdoors in the Northeast?
Tree peonies (Paeonia suffruticosa) are quite hardy plants (Zones 4-8) that are easy to grow. Tree peonies are shrubs with multiple woody stems. Some can grow up to 10 feet tall, though this would take approximately 50 years.
They do best in rich, loamy soil. The soil must be well drained but retain adequate moisture during the flowering season. They prefer a sunny location, so plant your tree peony where it will receive dappled sunshine all day, or 5 hours of direct sunlight a day. They do not do well in the shade or in areas that become waterlogged (including areas watered by automatic sprinklers). Tree peonies do not tolerate acid soils (below 6.0); ideal soil pH is between 6.5 and 7.0.
Remember that tree peonies grow larger than herbaceous peonies, so space the plants 3-4 feet apart. Feed in spring and summer with a weak solution of fish-seaweed solution about every 14-21 days. Compost is also a good amendment. Do not fertilize until after the leaves turn green, and end feeding in late summer. Buds are formed by late summer for next spring's bloom.
Tree peonies may need 4-5 years of growth before they will produce blooms.
For more information, see from Cornell Cooperative Extension's peony fact sheet.
For tips on a variety of gardening topics, see our Plant Information Guides.
- Courtesy of NYBG Plant Information Service