About Woody Peonies
Not Trees, But Shrubs With ‘Other Worldly’ Flowers
Peonies With Persistent Perennial Stems
Often incorrectly referred to as ‘tree peonies’, the woody peonies are actually relatively small shrubs, not trees. This group is characterized by strong woody stems that are perennial in nature, meaning that they remain above the ground and re-sprout for several years.
Hybrids are derived from crosses involving the woody shrub species found primarily in China which were grown for centuries in temperate gardens. Flowers may vary in size from a few inches in species like Paeonia delavayi, to over 9 inches in some of the named cultivars. Plants are long lived, with appropriate care and can gracefully overlook a garden for a lifetime.
Like herbaceous peonies, woody peonies require a period of cold dormancy for long term health. The woody peonies can be divided into four main groups: suffruticosa, rockii hybrids, species and the lutea hybrids. Each has different plant habits, floral characteristics and hardiness. Woody peonies can be grown in nearly all of the plant hardiness zones found within the United States, except for the warmest and coldest. With a bit of research, appropriate subjects from one or more of the woody peony groups should perform well no matter where you garden.
Growing and Planting Woody Peonies
Not Difficult to Grow, Just a Few Gardening Adjustments
Woody Peony culture is not all that different than for herbaceous peonies, but a few simple adjustments are helpful in getting the best from your plants. The main difference in their culture is the depth in which the root system is initially planted-deep. Since many ‘woodies’ are purchased as grafts (plants with a herbaceous nurse root) they require a planting depth of at least 4 inches, so that the plants can produce their own roots from buried stem(s). This simple act insures good rooting, but also insures survival of the plant in cases where stems are lost to above ground conditions.
Different woody peony groups can be selected for winter hardiness, but most can be grown with excellent results in USA Hardiness Zones 4b to 8. In the coldest zones Rockii hybrids are recommended and somewhat warmer zones do well with all types. The lutea hybrids often lose stems during cold winters, but if planted properly, will easily regrow them from below the ground. Through the selection of quality cultivars that are suited for the climate they will be grown in, woody peonies are something that should provide years of enjoyment. See Additional Resources below for further information.
Propagation Woody Peonies
Grafting and Starting From Seed
Propagation is the act of increasing the number of plants from a single peony. Sharing a favorite peony with a friend, creating more for the landscape, growing new varieties from seed, or rescuing a classic heritage variety are all great reasons to propagate a ‘woody’.
The primary method of clonal (copying) propagation for ‘woodies’ is through the procedure of grafting, that is the joining of woody peony stem to herbaceous peony root. The procedure is not all that difficult, but requires practice and skill.
If producing something completely new is desired, then growing them from seed is the method of choice. Woody peonies are easily grown from seed and the resulting plants are often worthy of the effort.
Division is possible in some cultivars, but is more difficult due to plant configuration. Generally, dividing woody peonies should be left to the experienced grower.
Whatever method is chosen, all are interesting and will provide hours of enjoyment. Resulting plants are great additions to your own garden or an admiring friend’s.
For further information, see Additional Resources below.