With their dramatic, showstopping blooms and sweet scent, peonies make a gorgeous addition to any bouquet or garden. Although pink peonies are a fan favorite, they come in a range of other colors. Peony plants may look delicate and fragile, but with the proper conditions they prove themselves to be a hardy perennial.
Peonies come in three main types: herbaceous, tree, and itoh. The most common is the herbaceous peony—the traditional garden peony (Paeonia lactiflora, best known for the popular ‘Sarah Bernhardt’ variety). These plants give off the strongest fragrance, which peonies are known for. As its name suggests, herbaceous peony doesn’t form woody material. Rather, all of its leaves grow from the ground. This also makes it the shortest plant of the peony types. Garden peonies come in typical peony colors such as pink, red, and white.
On the other hand, the tree peony grows tall from a trunk-like base (Paeonia suffruticosa or Paeonia lemoinei, also called deciduous peony, including varieties such as ‘Kansas Double’). Tree peonies are more expensive and grow at a slower pace.
The itoh peony, or intersectional peony (Paeonia lemoinei x Paeonia lactiflora), is a hybrid of the first two types. Itoh peonies offer more unusual colors, such as orange and yellow. Some varieties include ‘Cora Louise’ and ‘Bartzella’. They grow to a middle height between the garden and tree types.
Peonies are sold as bare-root tubers or as divisions of a young peony plant. Plant them in the fall, a few weeks before the first frost. If you need to move an established plant, this is also the time to do it. If you must plant in the spring, check that the ground is workable and that there's no risk of frost. Know that spring-planted peonies will usually lag a year behind fall-planted peonies.
Space peony plants 3-4 feet apart to allow them plenty of room to grow. A sure way for a plant to lack blooms is to plant it too deeply—peonies shouldn’t be placed more than 2 inches below the soil level. Otherwise, they’ll still send out shoots but they won’t flower. Plant your peony in full sun and well-drained soil. Make sure the spot you choose will allow the plant to have undisturbed roots. Give it shelter from wind, but don’t plant it too close to other trees or shrubs or the plants will compete for resources.
Water peonies at the base of the plant rather than on the foliage. Give them enough water to dampen the top 5 inches of soil. Continue to water your plants even after the flowers have wilted; the plants still need water to thrive.
To fertilize adult peonies, apply bonemeal, compost, or well-rotted manure in early summer as a soil amendment. Be careful not to use fertilizer near young shoots and stems. Use a fertilizer with higher levels of phosphorus (P) and potassium (K). Avoid nitrogen-heavy (N) fertilizers. These will give you good foliage growth but discourage strong blooms.
You may see lots of ants on peonies. Don’t fret—they won’t harm your plant! Just ignore them and they’ll eventually leave to feed elsewhere. You should inspect your plants for signs of common peony diseases, though. Here are a few to watch out for:
Botrytis blight: Happens in damp seasons when leaves get too wet and develop dark gray mold.
Powdery mildew: Mildew shows up as a white powder. It’s unattractive more than it is harmful to your plant.
Peony blotch: Also known as red spot or the measles for the color of the lesions. It won’t kill your plant, but it does disfigure it.
Peony wilt: A fungal infection in the soil that leads to destruction of the leaves and stems. Unfortunately, it usually results in plant death.
It’s spring and your peonies are in full bloom. After they’ve put on their show, a little TLC will ensure that they come back even stronger next year. Deadheading, or removing faded flowers, helps the plant save energy for next year’s blooms and prevents fungal diseases. If you're growing tree peonies, prune them in late spring. Be sure to remove any damaged wood. Make your cuts at an angle, right above outward-facing buds. You should cut back peonies just once a year. Wait until fall frost has killed off the foliage to do so. In the spring you’ll have a healthy plant ready to bloom again.