New Intersectional Peonies Deserve A Wow!

Photo: tree peony at Staten Island Botanical Gardens
Itoh or Intersectional Hybrid Peonies (Paeonia spp.) represent a huge breakthrough in tissue culture propagation. Inherited from the tree peony is attractive dissected foliage. They are extremely winter hardy like the herbaceous types.


Plants grow two to three feet tall and wide. Strong sturdy stems support the huge flowers which size up to 10" across. Flowers are single, semi-double or double, and available in a wide range of colors including yellow. Flowers stand upright even in heavy rain and require no staking. Bloom time is longer due to additional flowers being produced on side shoots.

Peonies are long-lived, growing in the same location for decades. They need to be properly nourished annually. Peonies prefer full to part sun (minimum of 6 hours per day), average moisture and well-drained soil which is enriched with compost or mulch annually.

Bare-root peonies should only be planted in the fall as this coincides with the time that their tubers develop most of their feeder roots. Container-grown peonies can be planted at any time. Itoh hybrids demonstrate good resistance to peony blight (Botrytis paeoniae).

Proper planting depth is very important for peonies. The crown should be planted 1½ - 2 inches below soil level. If the eyes have already begun to grow, the new growth may be set slightly above the surface.

Itoh peonies are now available through e-commerce nurseries.

Tips on Planting Peonies

Peonies (herbaceous types) are old-fashioned perennial favorites garnering new attention from 21st century gardeners. Their gorgeous spring flowers stand tall above the lush shrubbery growth.

This fall, plant dormant bare-root divisions of herbaceous peonies purchased from a mail-order nursery or a nearby garden center. Each division must exhibit 3 to 5 eyes (buds). Space plants a minimum of three feet apart.

Good air circulation around plants is important to prevent potential foliar and flower diseases. Avoid windy areas and shelter plants from harsh summer sun and heat in warmer climates (USDA zones 7-9).

Peonies thrive in gardens for 20 or more years. Select a sunny spot with well-drained garden soil and enrich with generous amounts of compost or well-rotted manure. A soil pH between 6 and 7 is ideal. Feed peonies with a slow release fertilizer in early spring the same as you would nourish flowering shrubs.

A critical digging step is the planting depth. Do not cover the growing eyes with more than 1 inch of soil. Setting the new plant too deep may delay or even prevent flowering. Water the newly planted peonies and cover the bed with 2-3 inches of loose ground up leaves or bark mulch. Likely, the peonies will bloom next spring and many years thereafter.

Tree peony culture will be discussed in a future blog.

Truly, Fall Is For Planting

Photo: Fall displays have arrived at area garden centers with this lovely bin of gourds

The seasonal theme at garden centers today is "Fall is for Planting". Plant sales are everywhere. If you have recently purchased a home and your budget is tight, buy yourself an early, but practicable holiday gift- a deciduous shade tree planted along the southwest side of the home. In a few short years, this tree will reward you with valuable shade and lower summer cooling bills.

Some good deciduous choices are red maple, green ash, tulip poplar, sweetgum, willow oak, and basswood. Garden centers push to reduce store inventories, saving you 30%-50% off the list price. I offer these six basic landscape planting tips:

1. Plant only deciduous trees in the front of your home, and evergreen trees (pines, hollies, hemlock, etc.) elsewhere
2. Dig a hole three times wider and shallow enough to accomodate the diameter of the root ball
3. Plant shallow, barely covering the root ball and add no soil amendments
4. Apply three inches of an organic mulch (wood chips, pine straw or compost) over the surface
width of the planting hole and do not pile mulch up against the trunk
5. Slowly pour a minimum of 10 gallons of water to each tree after planting
6. Do not fertilize fall-planted trees and shrubs until late February or March.