Don’t you just love the parade of flowers that we are treated to in the spring? First there were crocuses, daffodils and tulips. Then flowering crabapples, cherries, plums and pears lit up gardens around town with their delicate blossoms. And any day now, peonies will be adding their amazing beauty to the local scene.
It’s not uncommon for folks on garden tours to stop dead in their tracks upon seeing a blooming peony and know immediately that is what they want in their own garden.
But where do peonies come from and how do you grow them?
Alan Tower, owner of Tower Perennial Gardens, knows. After all, he’s had a lifelong fascination with peonies and has been supplying gardeners with them for years.
“China is the home of the peony,” Tower said. “They’ve been cultivating the peony for about 1,500 years. It’s been the national flower there, where they call the tree peony the king of flowers and the herbaceous peony the queen. It’s also revered in Japan and India.”
There are three main types of peonies: herbaceous, tree and intersectional.
Herbaceous peonies become fully dormant in the winter. They grow up from the ground each spring and their stems are not woody.
“They give you plant material that’s ideal for cutting,” Tower said. “They have good long stems for making bouquets, which is one of the greatest things about the peonies. They’re amazing in a vase.”
The tree peony is a woody plant that loses its leaves in the winter while the stems remain aboveground. Tower explained that they emerge from dormancy extremely early, when nighttime temperatures are still down in the 20s. Their foliage is very resistant to damage from freezing.
Intersectional peonies, also called Itoh peonies, are hybrids between herbaceous and tree peonies.
“I love what a tree peony is able to give you – a big shrub with enormous blooms that you cut individually and float in a bowl – and you are pretty much stuck with doing that with the intersectionals because they don’t have the long stems,” Tower said. “But they are very hardy, they grow well here and are deer-resistant.
“The intersectionals were best known for bringing the color yellow into the small peony world. That’s how they got my attention. An example of this is Bartzella.”
Peonies grow best with at least six hours of full sun per day, but will also do well in filtered light. They should be watered well, on a regular basis. Tower recommends amending the soil with a high-quality compost at the time of planting. Other than that, they don’t require annual fertilizing.
When it comes to planting peonies, timing and planting depth are everything.
Potted plants can be planted throughout the season because their roots won’t be disturbed in the process. Bare-root peonies should only be planted in the fall.
“The most fundamental difference between a tree and a herbaceous peony is the planting depth,” Tower said. “Herbaceous peonies must be planted very shallowly, where the growing points of the roots are no more than 1 to 1 1/2 inches below the soil surface. If you plant them too deeply, they’ll never bloom.”
Conversely, tree peonies like to be planted deeply. Tower suggests planting them 6 to 8 inches deeper than the container they were growing in. This causes them to form a stronger root system.
“(Tree) peonies and tomatoes are about the only things that appreciate being planted more deeply. You want those plants to start growing their own roots,” he said.
Peonies don’t necessarily need to be divided but if you have to relocate or divide any type of peony, the only time to do it is in the fall. Tower believes it’s important to let the plants get large and old so they can make a big splash in the garden.
Most gardeners probably think all peonies require some type of support but Tower said the majority don’t.
“You certainly don’t need a cage from day one,” he advised. “Let the plant grow over a couple of years to develop the strength and support they need and see what happens. If, after a few years, the plant still flops over, then that’s the time to get a support for it.
“The best type of support is a peony ring. A tomato cage looks awful; if you’re going to display your peony in the garden, make it attractive. There are a number of iron-working places in town that can custom-make peony rings for you.”
Tower had no difficulty summing up his fascination with peonies. “They’re all beautiful,” he said. “My favorite one is always the one I’m looking at. They certainly earn their keep with their blooms.”