Itoh peonies, also known as intersectional peonies, have traits in common with both its tree and herbaceous parent plants. They produce huge, long-lasting blooms and sturdy stems that don’t need to be staked, just like tree peonies. Additionally, they have rich, deeply lobed foliage that is dark green and last into autumn.
While the flowers may persist longer if they receive some mild shade, the foliage will grow more densely and healthily in full sun. Itohs have numerous blooms and produce more blooms. They are capable of strong growth up to 3 feet (1 m) in height and 4 feet (1 m) in width. Additionally resistant to peony blight are Itoh peonies.
Plant Itoh peonies in rich, well-drained soil in full sun to partial shade. Peonies from Itoh are vulnerable to excess nitrogen. Use a fertilizer with a low level of nitrogen, such as 4-10-12, when fertilizing in the spring and summer. In the late summer and early fall, avoid fertilizing peonies.
Over the course of the spring and summer, itohs can be deadheaded as necessary. Cut back Itoh peony in the fall to a height of 4-6 inches (10–15 cm) above the earth. Itoh peonies will reappear from the ground in the spring like herbaceous peonies do. Itoh peonies can be divided in the fall in the same way that herbaceous peonies are divided.
Do you trim Itoh peonies back?
It’s simple to add peonies to your landscape. In most areas, place plants in full light. Peonies planted in shadow in colder climates will have weak stems and fewer blossoms. Choose a location with afternoon shade if you live in a warmer climate or if springs are hot and dry. Plant in loamy soil that drains well or is average. Peonies prefer soil that is moist but not saturated with water. If necessary, add compost before planting.
Planting Steps for Herbaceous and Intersectional (Itoh) Peonies
- Select a location with well-drained soil that is far from any rival roots. Peonies grow well when given years of uninterrupted growth in the same spot.
- Create a hole that is the length of the roots and 12″ wide. Now is the time to fill the bottom of the hole with any compost. With the eyes (buds) facing up, plant the roots 1 to 2 inches beneath the surface of the soil. Plant them 2-3 feet apart if you’re planting more than one to give yourself enough room. The peony won’t bloom if it is planted too deeply. Visit our planting manual for a thorough explanation.
- Backfill the area surrounding the roots gradually, making sure there are no air pockets, and apply pressure to compact the soil.
- Once the plant is placed, water it gently all around. To control weed growth as well as the warmth and moisture of the soil, use a light mulch or chopped leaves. Unless it rains or there is a lot of moisture, water will be needed every day for 5 days in the morning or evening. Don’t overwater your plants or the roots may rot.
Planting Tree Peonies
Different from herbaceous and intersectional itoh peony, planting tree peonies.
- Select a location with well-drained soil that is far from any rival roots. If grown in the same spot for years without being disturbed, tree peonies thrive.
- Dig a hole about 2 feet deep, the length of the roots, and about 1 foot wide to accommodate the roots and leave some room for growth. Now is the time to fill the bottom of the hole with any compost. Plant them 2-3 feet apart if you’re planting more than one to give yourself enough room.
- Once the plant is placed, water it gently all around. When watering, wait until the earth has dried out or until it hasn’t rained. Water is necessary for tree peony to produce root growth, but too much water will cause them to decay.
Aftercare
Expect the roots of peony to produce 2–5 leaf shoots and 1-2 flowers in their first year of growth. Two years later, the plant is twice as big and has twice as many blooms. Peonies will be large and bushy, with loads of foliage and blooms, by their fourth or fifth year.
Staking
Itoh and tree peonies don’t need staking, but once established, the majority of herbaceous peonies produce large flowers that are frequently too heavy for their stems. You don’t have to stake them, but if you don’t, the result will be large, gorgeous blossoms that droop. Use peony rings to maintain their erect position after you have a healthy clump. The rings are simply wheel-shaped wire arrangements that rise above the peony when the plant emerges in the spring and resemble a small wire table. The peony ring is positioned with upright supports so that the shoots will push through the round wire bale. Of course, the foliage quickly covers the ring, and before the flowers even open, you have a gorgeously supported cluster. What stores carry peony rings? Gardeners Supply is something we advise.
Pruning/Trimming
After the blossoms have faded, cut off the spent flowers from herbaceous and (itoh) intersectional peonies at the point where the stem and foliage meet. For the balance of the growing season, leave the leaves alone. The leaves will first turn yellow before wilting as fall approaches and the weather cools. Trim back all leaves on herbaceous peonies to a height of about 3″ from the ground. As a result, the plant is kept neat and new growth can sprout without risking plant damage. Since itoh peonies are a hybrid of both herbaceous and tree peonies, they should be handled similarly in the fall. It is recommended to prune the plant once it has reached maturity so that the hard wood portion of the stem is left and the herbaceous portion is cut off. In order to distinguish between the hard wood stem and the herbaceous green stem when the leaves wither, it is recommended to leave peonies alone during their first year of growth. Itoh peony typically leave 4-5 inches of firm wood above ground when they are grown.
Different pruning methods are needed for tree peony. Just below the faded blossoms, cut the stem. Trimming the stem too much will prevent growth the next year. Next year’s woody branch will be formed from this year’s green shoots. So let the shrub alone in the fall rather than cutting it down to the ground. The optimum time to prune a mature tree peony if it needs to be shaped is shortly after it blooms. Don’t cut too much of the tree because doing so can seriously harm the plant.
Fertilizer
It’s not necessary to fertilize peonies every year. It is advisable to put them in a fertile environment. After peonies have blossomed every couple of years, spread bonemeal, compost, or well-rotted manure in the early summer.
Do Itoh peonies have several blooms?
At my property in Bedford, New York, I’ll have more stunning peonies blooming than ever in the spring.
I simply like peonies and have always been a collector of them. At one area of the farm, I have a lengthy peony border planted beneath the semi-shade of colossal sugar maple trees. Just over the carriage road from my house, I have a huge bed that is exclusively planted with pink and white herbaceous peonies. I’ve also planted tree peonies in the garden that’s buried into the ground behind my summer house. I recently acquired a sizable collection of intersectional Itoh peonies grown by Monrovia, a nationwide wholesale nursery with a focus on well-cared-for shrubs, perennials, annuals, ferns, grasses, and conifers. I made the decision that the formal Summer House garden beds encircled by my boxwood hedges would be the ideal location for these hybrid peonies. I can’t wait to see them blossom in May after my gardeners planted about 50 yellow and salmon Itoh peonies yesterday.
I am a devoted and enthusiastic gardener, and I am constantly seeking for methods to make all of my garden beds more beautiful and interesting. I had already planned where I would put these peonies when they arrived. They all hail from Monrovia, where more than 18 different varieties of these are grown “Peonies from Itoh
This magnificent ‘Bartzella’ Itoh peony is one among the kinds we got. Itoh peonies are crossbreeds between tree peony and herbaceous peonies. In the 1940s, Dr. Toichi Itoh, a Japanese botanist, was the first to successfully mate tree peony pollen with herbaceous peony ovary. This one has extraordinarily big, vivid yellow blooms. The center is a richer yellow than the outer layers, which are initially a lighter shade of lemon meringue. Flares of red are hidden within the puffy flowers. Additionally, “Bartzella” smells a little peppery. (Monrovia photo by Doreen Wynja)
This Itoh peony is known as “Singing in the Rain,” and it has enormous, semi-double, creamy blooms with exquisite apricot-salmon flushes. The flowers are presented on long stalks that are ideal for cutting, and they have a gentle, pleasant aroma. (Monrovia photo by Doreen Wynja)
“Pink Double Dandy” is this. When in bloom, it displays a dense mound of dark green foliage above big, semi-double to double, faintly fragrant blooms on sturdy stalks. When ripe, the blossoms have a deep lavender-pink color. After then, the petals turn a light pink and the center’s collection of yellow stamens is visible. Leading Itoh Peony breeder Don Smith created this variety through hybridization. I’ll include a few of these pink peonies in my tree peony border. (Monrovia photo by Doreen Wynja)
I desired the formal rectangular beds behind my Summer House to be planted with the yellow and apricot peonies. To create way for the peony plants, the hostas were moved to a different location.
One of the beds is shown here, cleared and prepared for planting. Numerous white snowdrop bulbs that blossom in the spring are also present beneath the earth.
All of the peonies are neatly arranged in lines and are color-coded by Ryan in the bedsall.
To give these peony plenty of opportunity to grow, they are spaced about three feet apart. Peonies from Itoh produce lots of blooms. On a strong, mature plant, they can expand furiously to three feet tall and four feet wide, and they can produce up to 60 blooms in a second group.
Brian is shown here as he begins to sow more than 20 seeds in this bed. Itoh peonies, also known as intersectional peonies, have traits in common with both its tree and herbaceous parent plants. They produce huge, long-lasting blooms and sturdy stems that don’t need to be staked, just like tree peonies. Additionally, they have rich, deeply lobed foliage that is dark green and last into autumn. Additionally resistant to peony blight are Itoh peonies.
Even though these plants are currently dormant, notice all the stems. These are mature plants as well, so next year should see stunning blooms that measure up to eight inches wide.
The hole is first dug by Brian, at least twice as big as the plant. The ideal planting conditions for itoh peony include rich, well-drained soil and full sun to part shade.
After the hole is dug, Brian uses the potted plant to gauge its size.
The dirt around the hole and in it is then liberally fertilized by Brian. I typically say, “Your plants should eat if you do. For these plants, we’re using Roots fertilizer with mycorrhizal fungi, which improves water and nutrient absorption while helping transplant survival. Itoh peony are susceptible to high nitrogen levels, so use a fertilizer with a low level of nitrogen when fertilizing in the spring and summer.
These peony are in wonderful shape, and Brian gently removes the plant from its container. Then, in order to promote growth, he gently loosens the roots with his hands.
The tops of the stems on the peony in this picture should be just level with the ground.
This peony is the ideal height and should survive the cold weather with no problems.
Brian then fills the hole with soil, making sure it is tightly packed and that all of the stems are completely encased.
Brian makes sure the peonies are planted in absolutely straight lines down the bed by using the empty upturned pots as markers because the plants are trimmed down and don’t currently have any leaf.
Following the planting of all the peonies in the section, the entire area is top dressed with an additional layer of soil before being raked evenly. Due to the numerous side buds that bloom in succession, these Itoh peonies are late midseason plants and will flower in late spring to early summer for three to four weeks.
Next May, these beds will be awash in color. These Itoh peony are strong and resilient to the cold. These aromatic plants can live for 100 years or even longer if planted and cared for properly.
What distinguishes peony from Itoh?
Itoh peonies, which are hybrids of herbaceous and tree peonies, thrive in a variety of conditions and have magnificent foliage, enormous blooms, and a wide range of color options. In Zones 4–9, hardy.
If you delve deeper into the magnificent beauty of the Itoh peony, you’ll find an inspirational tale of tenacity. An Itoh peony is produced by crossing a typical garden peony (Paeonia lactiflora) with the eye-catching tree peony (Paenoia suffruticosa). For many years, plant breeders believed that because these two peony kinds have such dissimilar parents, a successful hybrid of them would not be possible.
Toichi Itoh, a Japanese plantsman, worked tirelessly to complete this cross. Itoh made this pursuit his life’s work and succeeded in 1948 by breeding the tree peony (Paeonia lactiflora ‘Kakoden’) with the herbaceous peony (Paenoia x lemoinei). 36 plants were born from the productive cross. Nine of those plants exhibited tree peony traits and were dubbed Itoh peonies or Itoh Hybrid peonies. Intersectional peonies and intersectional hybrids are occasionally mentioned. These plants are Itoh peony subspecies.
There were so few Itoh peonies available when they were originally made available to the public and presented to the nursery industry that the cost of one plant exceeded $1,000. The lengthy process of raising these plants to the point where they could produce divisions was reflected in the expensive price tag. The cost of Itoh peony has decreased to between $50 and $100 per plant thanks to the use of tissue culture techniques, which multiply them more quickly.
Because they produce flowers and foliage that resemble tree peonies on a plant that acts like a perennial, Itoh peonies are worth paying any price for. Each year, when the first frost hits, the plant dies back to the soil, and the next spring, fresh growth appears from the ground. This puts an end to concerns about a tree peony’s bloom buds on woody stems being damaged by a late spring frost.
When an Itoh peony’s flower buds open, they reveal big, tree peony-type blooms that are dinner-plate size and come in a variety of colors, including golds and yellows that are less common in herbaceous peony varieties. Despite the huge bloom heads, there is no need to anchor the plants because they have sturdy stems similar to those of a tree peony. A mature Itoh peony has a blooming season that can yield up to 50 blossoms.
The Itoh peony group achieves its optimum bloom time while the herbaceous peony group is completing. Itoh peonies often begin flowering when herbaceous peonies are in bloom. There is a strong, protracted floral display because many Itoh peony plants generate flowers from secondary buds that develop beneath the first flower. Three to four weeks are a luxuriously long flowering period for each Itoh peony plant.
In the garden, Itoh peony hybrids have strong resistance to powdery mildew, which afflicts herbaceous peonies, and botrytis blight, which frequently affects tree peonies. They are also deer-resistant. The Itoh peony group has blossoms that create excellent cut flowers, just like its peony progenitors. Itoh peony typically reach heights of 2 feet and a width of 3.5 feet.