Of all the flowers you can grow, peonies are often the most luxurious and spectacular blooms in an early summer garden. They are adaptable, durable perennials that will tolerate considerable insult as long as they have good drainage. Some plants are known to be a 100 years old.
Peonies, like roses, have an ancient pedigree dating back to at least 1000 BC. For centuries, peonies were grown primarily for their seeds, leaves, and roots which were widely used for a variety of ills. The medical value faded in Western cultures as it gained favor with horticulturists, though there is now an renewed interest. Peonies are also a favorite of artists in almost every culture.
Among the many reasons to grow peonies are fragrance and color. Doubles are extremely fragrant whereas single blooms are much lighter. Some have no scent at all. Colors range from white, cream, and ivory through myriad pinks, roses, and dark reds. Several lovely yellows, which are intersectional crosses between herbaceous and tree forms, are also available, though the cost for these rare peonies is high.
Peonies make beautiful cut flowers, though you want to avoid completely denuding your plants, especially when young. Planted at the back of a perennial bed, the deeply cut, glossy green foliage makes a pleasing background throughout the summer for other plants.
Peonies are available in dozens of varieties including herbaceous and tree forms, The herbaceous Paeonia lactiflora, a native of Siberia, is the Chinese peony with the large, opulent flowers.
Tree peonies (Paeonia suffruticosa) are deciduous shrubs that lose their leaves every fall. They are usually between 3–4 feet tall, but can be shorter or taller depending on the variety. Some can grow as tall as 6 feet.
They were cultivated first by the Chinese whose work resulted in large, double flowers. Once in Japanese hands, however, the peony were bred for a lighter, simpler flower that is known as the Japanese form. Imported into Europe, the peony continued its evolution as breeders created new cultivars and shared with their counterparts on the other side of the planet.
Herbaceous peonies, like many perennials die back completely in the fall.
Peonies come in many different sizes and habits as well. The tiny, fern-leaf peony with its fine, delicate foliage is small and less than a foot and a half tall. Other shrubby varieties like tree peonies are considerably taller. Many, especially the large Chinese types with their oversized blooms, require staking. Japanese type peonies with lighter flowers often have a more upright habit and are not as likely to need support.
Peonies are extremely easy to grow in many areas from zone 3 to 8. They like full sun in all but the hottest climates. Too little sun and you will have few blooms. Even if you have an hour or two of full sun and partial shade the rest of the day, your flower show will suffer. However, if you have long, hot summers a little light shade, especially in the afternoon, can be beneficial and preserve the color of your flowers.
Soil should be well drained and rich. Poor soil with poor drainage will annihilate your peonies quickly.
Peonies can be slow growers, especially if you start with small divisions. Young plants can take several years before flowering.
Peonies need good nutrition to produce those spectacular flowers. However, unless your soil actually needs amending (sandy, for example) adding a good compost in the fall should do the trick. If you need to add a fertilizer, scratch a granular type into the soil in spring when you fertilize the rest of your perennials.
Plant so the top of the divisions are no deeper than two inches.
If you need to plant or transplant your peony, do it in the fall. Grandma used to say that peonies don't like being transplanted, and that is certainly true of mature plants. If you must move your plant, give your peony plenty of time to develop a strong, vigorous root system before it faces the double stresses of blooming and summer heat. Experts also advise dividing your mature peony rather than trying to transplant it intact. The bonus is two fast growing plants that may bloom the first year after transplant. A plant that is not divided may not bloom for several years.
Let the plant die back in the fall and don't rush to cut the foliage. After blooming, peonies offer lovely foliage which will allow the roots to store the nutrition it needs for next seasons flowers. Wait until the first hard frost, then cut stems back to the ground.
Peonies are susceptible to fungal infections. The best way to control the problem is to make sure they have good drainage, air circulation, and clean up clippings in the fall so pathogens don't have a place to live.
Peonies do grow in pots, but are successful only in large, well-draining containers that can accommodate their huge root system. They need to be fed often (once a month) and protected from very cold temperatures. Peonies prefer to be planted in the ground, so your success may vary depending on your diligence.
That said, peonies really need a good cold period of dormancy. Like many other perennial flowers such as lilacs, peonies need not freeze to produce their summer bloom, but being aware of how cold your winters are means you will be able to select the most appropriate peony for your climate.
Each peony variety blooms for only a week or two at the most. To get a more gratifying peony season, choose several varieties with different bloom times.
To plan perennial beds, a qualified landscape professional at UpdateRenovate can help.