Itoh hybrids are the newest and arguably most exciting peony group. They combine the best of both worlds: the lavish flowers and foliage of tree peonies with the toughness and hardiness of herbaceous ones. Among them you find rare yellows, corals and apricots. Here is where Itoh hybrids come from, how they differ, the best varieties and how to plant and care for them.
Japanese breeder Toichi Itoh produced the first such hybrid in 1948 by crossing a herbaceous Chinese peony with a yellow tree peony. He did not live to see his seedlings flower, but his work continued, and in the 1970s Yellow Crown, Yellow Dream and Yellow Emperor reached the USA.
Botanically they are intersectional hybrids; gardeners call them Itoh peonies after their creator.
How they differ from other peonies
From tree peonies they took the flower shape, cut foliage and rare colours; from herbaceous peonies, the habit of dying back in winter and regrowing from the roots. The stem bases become partly woody.
The plant is compact at 60–90 cm with strong stems, so flowers do not flop after rain. Side buds extend flowering to 3–4 weeks, longer than any other group.
Bartzella has lemon-yellow double flowers up to 20 cm and a light scent — the world’s most popular Itoh. Garden Treasure is golden yellow and very free-flowering.
Cora Louise is white with a lilac central flare; Julia Rose shifts from cherry to apricot and yellow; Hillary is creamy pink with a raspberry centre.
Scarlet Heaven has rich red semi-double blooms, Morning Lilac lilac-pink and Lollipop yellow with red streaks.
Planting and care
Plant them like herbaceous peonies, in late August or September, in a sunny spot with loose, neutral soil and the buds 3–5 cm deep. More in when to transplant peonies.
Feed and water as for ordinary peonies. Itohs suffer less from grey mould and usually need no staking.
In autumn do not cut stems to the ground: leave 5–10 cm, as the woody part may carry next year’s buds. Only young plants need winter cover.
When to expect flowers
The first flowers appear 2–3 years after planting, and mature plants carry 30–50 buds. They bloom between tree and herbaceous peonies, around late May to June.
Graduated from Taras Shevchenko National University of Kyiv, Institute of Biology and Medicine (2001). BSc in Biology, MSc in Horticulture. Writes about plants, works at a garden centre selecting and repotting plants, and contributes to plant reference guides.
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