5 Things To Do After Peonies Bloom for an Even Better Show Next Year

Peonies are among the garden's most sensational blooms. With their pillowy, cloud-like petals and signature range of hues, it's easy to see why they earned the title "king of flowers" in China. However, their beauty is only one aspect of their appeal. As perennials, peonies can thrive for decades when given the right care.

The catch? What you do after bloom season can have a major impact on next year's display. Here, we asked gardening experts how to keep peonies healthy, vigorous, and flowering reliably.

Remove Faded Flowers

Once a peony's blooms have run their course and begin dropping petals, it's time to deadhead them. Removing spent flowers prevents the plant from directing energy into seed production and instead encourages it to strengthen its roots and develop next year's buds.

"For your garden's best overall aesthetic, I remove the bloom by cutting just above the first tri-lobed leaf," says Carol Adelman, owner of Adelman Peony Gardens.

Herbaceous peonies should be deadheaded by cutting spent blooms just above the first strong leaf while leaving healthy foliage in place until fall. Tree peonies, however, require only the faded flowers to be removed; their stems should not be shortened.

Leave Stems and Foliage Intact

By midsummer, peony foliage can start to look tired. One of the most common mistakes gardeners make is cutting it back too soon for a tidier appearance. “To encourage the most vigorous peony plants and bloom over time, let the foliage and stems stand through the summer and fall,” says Adelman. Removing them early can reduce flowering for the following year. 

For bush peonies and intersectional peonies, Adelman recommends cutting foliage back to the ground after frost in late fall. “If you receive a hard frost before then, go ahead and cut these peonies to the ground,” she says. “Place the foliage and stems in the garbage to help prevent any fungus—or other disease that may reside there—from spreading.”

Tree peonies, however, shouldn't be cut back in the fall. Instead, allow them to shed their leaves naturally before removing any debris.

Water Consistently

While established peonies are relatively low-maintenance and impressively drought-tolerant, prolonged stress can still impact their long-term bloom performance. Few people know this better than David Michener, curator at the University of Michigan's Matthaei Botanical Gardens and Nichols Arboretum. There, he helps care for the W.E. Upjohn Peony Garden, which is home to nearly 800 peonies.

In his garden, Michener notes that established plants rely on rain for all their water during the growing season. "Our exception is for new plants, which may have supplemental deep watering by hand. There is no irrigation system,” he says. 

That doesn't mean gardeners should ignore peonies during an especially dry summer. "In drier parts of the country, or for gardeners not blessed with moisture-retentive but well-drained glacial clay loam, occasional deep watering may be useful if the foliage begins to wilt and not recover overnight," Michener says.

Summer is a particularly important time for peonies, as the plants are developing roots and forming the buds that will become next year's flowers. If conditions turn dry, a thorough soaking once a week is far more beneficial than frequent shallow watering. The goal is evenly moist soil, not constantly wet soil. Before reaching for the hose, check the soil first. If it still feels moist a few inches below the surface, your peony likely has all the water it needs.

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Give Them a Targeted Feeding

"It's best to fertilize in summer and early fall to ensure that the peony has adequate nutrition to form flower buds for next year," says Dan Furman, second-generation nursery grower and co-owner of Cricket Hill Garden. "Peonies have a flush of new roots in early fall when the plant gathers nutrients for the following season.” 

Furman recommends fertilizing with bone meal or another high-phosphorus fertilizer in summer to ensure that it will be available for the plant when it needs it. To do so, apply a light dose of tulip or daffodil fertilizer in the fall. Rather than sprinkling fertilizer directly at the base of the plant, Adelman recommends spreading it beneath the outer leaves, several inches away from the crown. "The fine roots which make use of those nutrients reside in that area," she says.

Check for Disease

Peonies are generally resilient plants, but they can be vulnerable to fungal diseases, particularly during cool, damp weather or when grown in areas with poor air circulation. "The most common summer fungus on peonies is powdery mildew," says Furman. If the disease becomes a recurring problem, he recommends first evaluating the plant's growing conditions, rather than immediately reaching for a treatment.

"Is there plenty of room around the plant to allow for good airflow? Does the plant receive adequate sunlight—preferably six hours?" Furman says. "If the answer to either of these questions is no, then you might consider moving the plant when it is dormant in early fall."

Prevention begins with good maintenance habits. Give peonies ample space and ensure they receive plenty of sun. Water at the base of the plant instead of overhead to keep foliage dry. For added protection, some gardeners apply a preventative fungicide in early spring, particularly in areas where botrytis has been a recurring issue.