The rage of peonies - Intersectional Itoh flowering garden plants.
They are peonies of perfection, with some of the finest qualities of all peonies: exotic flowers; pleasant fragrance; upright plant habitat, unique colors and winter hardiness.
Intersectional peonies are a hybrid cross between a bush and a tree peony, thus the name ‘intersectional’. They are often referred to as Itoh peonies, after the first successful breeder of this type of peony, Mr. Toichi Itoh. His quest for creating an intersectional peony cross reportedly came to fruition in the late 1940’s, after years of dedication. Because of his success, many other hybridizers found hope and inspiration in creating additional intersectional peonies. Mr. Itoh left a living legacy to the world with these most spectacular, flowering garden plants. Sadly, he passed away before seeing their first blooms. Fortunately, Louis Smirnow, a peony grower in New York contacted Mrs. Itoh and they arranged the transfer of the plants for future generations to enjoy. Mr. Smirnow was able to introduce the first Itoh peonies (Yellow Crown, Yellow Dream, Yellow Emperor and Yellow Heaven) in the 1970’s, and the stampede for such magnificence began.
Incredible Peony Flowers
While their large, showy flowers resemble those of the tree peony parent, the growth habitat is that of a bush peony. They come in single, semi-double and double flower forms, with petals silky smooth or delightfully ruffled. The color spectrum of selections ranges from solid tones to blends of multiple colors, many with contrasting ‘flares’ in the center. Clear, bright yellow; dark black-red; crisp white with lavender or purple flares; and, a kaleidoscope of colors are found in these peonies.
In early spring the primary ‘eyes’ (buds) on their root system sprout into new stems, each producing a flower. Many varieties also develop side buds, which produce additional, smaller blossoms on the same stem as the main flower. Prolific bloomers, they may produce 50 – 75+ blossoms on a single mature plant and tend to have a longer blooming period than most peonies. After blooming, most folk’s dead head; but, you can leave the spent flower to produce magnificent seed pods. They can be cut and dried to use in floral arrangements. You may even find a viable seed in one (although, that is elusive in intersectionals).
That Peony Foliage
The attractive foliage is serrated, like that of a tree peony. The leaves are shades of green or bronze, depending upon the variety. The plants display the flowers beautifully on stately, domed plants, making them excellent choices for landscaping. Once you see a few intersectional Itoh peonies, your eye will recognize the distinct foliage and flowers.
Oh, The Fragrance!
Let’s talk about fragrance. Itoh peonies have the most heavenly scented fragrances (I have only encountered one or two intersectional varieties that did not seem to have fragrance). I think of their fragrances as ‘sweet’ or ‘perfumed’ – absolutely outstanding. The flowers of ‘Bartzella’ and ‘Garden Treasure’ actually have a lemony fragrance.
Plant Habitat & Care
Gardeners love the upright plant habitat that never needs staking. They keep looking beautiful through winds and rains. In 17 years of growing these peonies, I have never seen an intersectional Itoh peony plant go down under the weight of rain. Love that!
Like all herbaceous peonies, they can thrive in the same garden spot for years (even decades) without needing to be divided. They come in many heights and widths, to fill small or large garden spots. On average they fill up a 3’ x 3’ space.
Care for an intersectional Itoh peony like any garden bush peony, including cutting stems to ground level each fall, as they go into dormancy for the winter. You’ll know when it’s time – they will start to lose their appeal and begin to look a bit ‘ratty’. It’s highly recommended to remove all peony stems and leaves from the garden each fall; rather than composting them. Sometimes people think their plant has died; but, it is just going dormant and is supposed to ‘die back’ each fall.
If you forget to cut back the stems in the fall, they will naturally deteriorate and turn mushy. Try to clean up the foliage as soon as you can. While these cultivars are rather disease resistant, leaving old, mushy peony foliage in the garden can invite unwanted fungal guests.
The underground roots are workhorses, growing quite large over the first 3 – 4 years. They store nutrients for stem and flower growth. Expect about 3 years to reach maturity from a newly planted root division or a transplant from a container.
Bare root peonies are planted in the fall and potted peonies may be transplanted spring or fall. Intersectional Itoh peonies can thrive in USDA zones 2-8 (they do like a winter chill). In warmer winter zones (USDA zone 9) planting roots closer to the surface, with just a smidge of soil over the eyes (buds) ensures greater success. While other herbaceous garden peonies only want one to two inches of soil over the eyes in USDA zones 2-8, the intersectional can take another inch of soil. Often, laying the root at an angle allows for easier planting, as the eyes tend to be more generous, on a longer root. As with other peonies, they love full sun; and will do fine in partial shade.
Peony plant growth is slow the first spring, as the roots develop. First year peonies may produce only a few stems – this is normal. While many flower the first year, it may take another year to get blossoms. By the third spring, you should have a glorious plant.
Fertilizing peonies is a matter of personal choice and/or soil quality. Many gardeners fertilize annually in the spring, others never fertilize their peonies and have excellent results. A 10-20-20 organic or synthetic bulb/flower fertilizer can be used in early spring. Be sure it is a slow release fertilizer if applied to potted plants, or it will burn the foliage. Follow recommendations from the label and apply near the drip line of the plant (a foot or so from center).
Peony hybridizers continue to introduce new varieties of stunning intersectional plants every year. It seems as though the array of colors and hues never ceases to amaze peony lovers.
Visit our peony fields this spring, take a look, smell the peonies…and, fall in love. We grow about 40 varieties of intersectional Itoh peonies - see them blooming from early May through early June.