Yellow intersectional peonies were first developed by Mr. Toichi Itoh of Japan in the 1940s. Summer Crush Hydrangea Plant with Raspberry Red or Neon Purple Blooms. Also known as intersectional Peonies, these hybrids arose 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.All the resulting offspring were vigorous plants with foliage similar to that of Tree Peonies… Uniquely yellow, extra-large flowers (6-8" across) form on a robust, winter-hardy … $51.84. Itohs can be deadheaded as needed throughout the spring and summer. A successful crossing of a tree peony and a bush peony, this hybrid exhibits only the best traits of its peony parents. Peonies … Itoh peonies have enormous flowers up to eight inches across, with undulating petals encircling a froth of yellow stamens. Product Overview. $39.07. Itoh peonies are sensitive to high levels of nitrogen. All the original Itoh cultivars were yellow, but today they come in a wide range of beautiful colors including coral, red, pink and white, as well as their signature buttery yellow. Do not fertilize peonies in late summer to fall. 'Yellow Crown' was one of the original introductions by Mr. Itoh. Endless Summer 2 Gal. Here’s a special opportunity to own an Itoh hybrid Peony. This item: Yellow Itoh Peony Prairie Charm Root. They are a cross between the tender tree peony and hardier herbaceous peonies. When fertilizing in spring and summer, be sure to use a fertilizer that contains a low level of nitrogen, like 4-10-12. In autumn, cut back Itoh peonies …