How to Grow and Divide Peonies
Take a close look at how to successfully grow and divide peonies.
Peonies are one of the oldest domesticated plants known to man; in fact, written records dating back to 4000 B.C. tell of their beauty and grace. Today, peonies are just as splendid as ever, and thanks to new and improved varieties, they're even easier to grow.
Since he was a little boy, peony grower Allan Rogers has been entranced by the power of the peony. His parents gave him one as a birthday present and that gift has lasted a lifetime.
"I had my first peony when I was 8 years old, which was 75 years ago," says Rogers. From that moment on, he was captivated, and it's easy to see why. The personality of the peony bloom changes as the day progresses, beginning shy and reserved during the cool hours of the morning then later unfolding a world of beauty as the day warms.
There are three popular types. Herbaceous peonies die back to the ground in the winter and are the type most folks are familiar with. The herbaceous peonies bloom early to mid-summer in most places.
The second type of peony is the tree peony, which is a woody-stemmed shrub that loses its leaves in the fall. You can expect blooms from these beauties in the spring.
Finally, intersectional peonies are a cross between tree and herbaceous peonies. For years hybridizers were unsuccessful at crossing the two until a Japanese nurseryman finally got it right. The results opened up a plethora of peonies for folks who thought they couldn't grow them.
"I'm a great fan of them because they're more disease-resistant and more rigorous," says Rogers. However, there is one caveat to growing peonies. They require a period of dormancy so the plant can store energy to grow and bloom the following year. In this case, dormancy means low temperatures. Peonies typically do poorly in places like Georgia, southern California and Florida. A peony has to have about 400 hours of cold - not freezing - temperatures, about 40 degrees. Containers and north-side plantings are common tricks for warmer locales. But ensure three months of dormancy for productive plants next year.
After 10 or so years of growth, you may notice smaller flowers and crowded stems. This usually means it's time to make more peony plants. "The right time to divide peonies is in the fall," says Rogers. "By that time they've finished their year's growth and have started to go dormant."
To simulate the foliage dying back in the fall, we cut the foliage back to the soil line. Rogers then recommends removing all the soil from the roots and giving them a good soaking with the hose. Rogers manipulates the roots to get a good look at where they separate easily, and that's where he makes the first cut.
"Every plant needs a crown, which is this part," says Rogers. "It puts up the shoots and puts down the roots." Each section should have three to five eyes which are where next year's new growth begins. You want enough eyes to create a lush plant. All the fine rootlets need to be pruned away and with good reason. Pests and diseases aren't a huge problem with peonies - with one exception: There are some root diseases that can severely restrict the growth of peonies. That's why it's so important to always cut off the tiny hair roots.
Dig deep and wide when planting peonies. A plant can mature to a width of five feet or so, and the hole should be prepped accordingly.
The most important thing about planting peonies is selecting a site. Choose a location with at least a half day of sun. More sun will give you more flowers, and light shade will keep the blooms fresher longer. Once the planting hole is worked to his pleasing, Rogers fertilizes with bone meal. The bone meal will take two to three years to break down, making it a simple, long-term investment.
When you plant, make sure the eyes of the peony are facing up and are planted no more than two inches deep. Cover with soil, tamp the ground firmly and water. As the plant grows, it will most likely need staking.
Peony flowers can get to be eight to nine inches in diameter and often need the added support. There are lots of ways to stake them, but Rogers prefers aluminum stakes. You may need more stakes over time to hold up the weight of the blooms.
Peonies can live for decades, getting more and more exquisite with each passing year. Where peonies go, ants will follow, because they love the sweet substance the plant exudes as it blooms. Don't worry, though, the ants won't hurt a thing. Also, if deer are a problem in your neck of the woods, consider planting peonies. The deer will take one bite and move onto something much tastier.