yellow peony at Brooklyn Botanic Gardens

Intersectional Peony

Intersectional Peonies are hybrids; they are derived from a cross between a white Herbaceous Peony (Paeonia lactiflora 'Kakoden') and a yellow hybrid Tree Peony (Paeonia x lemoinei) carried out in 1948 by Mr. Toichi Itoh. For this reason, they are also known as Itoh hybrids or Itoh peonies.
Intersectionals are valued because they are available in colours that traditional peonies can't produce — in particular, more intense shades of yellow, peach, and coral.  These plants have the lovely leaf form of the tree peonies, but die to the ground in the winter like herbaceous peonies. The plants are strong and healthy with a nice rounded bush form, but are generally shorter than most bush peonies.  Since they are recent introductions and are still in short supply, they are usually quite expensive.

Examples of some intersectional peony varieties are: Bartzella, Border Charm, Cora Louise, First Arrival, Garden Treasure, Hillary, Julia Rose, Sequestered Sunshine.