Whether your peony flowers are herbaceous or Japanese tree peonies, these six plant care tips are essential for healthy flower production in container gardens year after year.
You’ll need to plant, care for, and winter them over properly as well as provide just the right soil, sun, site conditions, water, and fertilizer. We’ll take them one at a time.
The Site
Peony flowers prefer a sunny location and will do best in from 6-8 hours of sunlight a day. Poor blooming and stunted plant growth can occur if they are placed in a too-shady site.They should also have good air circulation, so don’t crowd your cement or stone planters next to each other. Since these flowers are very sensitive to overly wet conditions, air circulation in container gardens is important.Herbaceous peonies come in early, mid-summer, and late-blooming cultivars, so you can enjoy them on your patio or deck all growing season. Once they bloom, if you want to extend the lush blossoms, move them into light shade.
Soil
Peonies do best in rich, well-draining soil. Adding compost to your potting soil, or any other well-broken down organic matter, will result in a healthy, bushy plants and large blooms.Peony flowers are particularly susceptible to fungal diseases, and can’t tolerate soggy roots. Make sure you have layers of pebbles or sand in the bottom of your flower pots to enhance the drainage. You can also add some lightening material (perlite or vermiculite) to the planting soil itself to ensure proper drainage.
Planting
You may purchase a tree peony or bush planted up, but they are also often sold in bare root form. Reliable vendors ship tuberous roots in the fall, which is the very best time to plant them. You can also plant in spring, but fall is by far the preferred time to plant or divide them.When you receive the roots, look for little reddish buds—these are the sites from which the plant will sprout next spring. Be sure to plant the roots with these little eyes facing upward and site properly in your container garden.And don’t bury them deep in the pot! The roots should be about two inches below the surface. If you’ve bought potted plants, you’ll put them in permanent containers so that the hard base is just below the soil surface.Peony flowers are hardy plants and need a cool period during their winter dormancy to bloom well. But if you live in a very cold climate with prolonged hard freezes (below 32 degrees, for instance), you should mulch the plants and also insulate the pots to over-winter them successfully. Some people do this, then sink them in their flower garden beds for wintering over.
Watering
These flowering perennials do need watering through the growing season, so the drainage factor is doubly important. Don’t allow the soil to become water-logged. If the soil is wet, don’t water. Wait until it dries out a bit, then water until you see water draining out the pot’s bottom.And one note about ants. Many people feel one of two ways about their presence (and they do seem to be present from the bud to bloom stage). The thought is that they either harm the blooms or are essential to the buds’ opening. Both are myths. Ants neither harm nor help your peony flowers. They just like the sweet buds and blooms, and are nothing to be concerned about.
Staking
Peony blooms are large and heavy. And the plants can grow to be four feet tall. So staking is very important. You can purchase special green wire hoops which should be put in place just as the stems begin to erupt in spring.These hoops encircle the entire plant and hold the many stems upright. But you need to purchase them prior to spring and be ready. If you wait too long after the stems begin to grow, the bush will be too large for you to properly stake it.
Maintenance
Once the peony flowers fade, remove them. The plant will continue to grow and then in fall, your plant will go dormant. This is the natural cycle, so don’t be concerned that the leaves and stalks die back.Because peonies are particularly prone to fungal infection, good plant culture is imperative. Be very sure your soil drains well, and remove spent blooms and cut back, then remove both leaves and stems as the plant goes dormant.If your peony does develop botrytis blight, which is the most prevalent disease problem, here are the symptoms. The stems can wilt and fall over. The rotting parts of the plant will turn blackish and you can see a gray mold develop.You can use a fungicide to help prevent the disease, but if your plant shows these signs, you’ll need to remove the affected portions immediately and discard. Don’t throw any diseased materials into your compost pile, though, since you don’t want to spread the disease spores throughout your compost.In addition to proper watering, care in plant clean up (both during the season and in preparation for winter dormancy) will greatly help reduce the potential for botrytis blight. Remove spent blooms and the rest of the plant above ground as it naturally dies back.