There’s so much to love about peonies: their ruffled petals, dazzling colors, and sweet-smelling aroma. Even a small cluster has the ability to add a show-stopping flair to any spring garden. Aside from their visually striking nature, peonies are a low-maintenance, eco-friendly, pest-resistant, hardy perennial, which is essentially a gardener’s dream!
Since peonies typically bloom from late April to early June, once the last flower fades, you might assume that your plant is good to go until the following spring. Although they’re largely easygoing, peonies need a little extra attention in the off-season, too. During the dog days of summer, in particular, heatwaves and dry spells can threaten next year’s blooms. “Although the flowers are gone, July and August are some of the most important months in a peony's growing cycle,” says Laura Kubes, owner of Minnesota-based Hidden Springs Peony Farm. “It’s when the leaves are soaking up energy from the sun and feeding it to the roots.” That stored energy is what supports the flowers’ spring growth.
If you’re experiencing a bout of hot, dry weather, horticulturists say there’s one important task that many gardeners neglect but that can make a massive difference for your future flowers. By tackling this chore now, you’ll give the buds a much-needed boost for more beautiful blooms next spring. If you’re wondering how to promote bigger and brighter spring-blooming peonies, don’t skip this essential midsummer care tip.
The Top Peony Care Task to Tackle in Summer
Although established peonies are drought-tolerant, hot, dry weather in July and August can cause future flower buds to decline early. That’s why experts agree that deeply watering your perennials during dry spells is one of the most important gardening chores you can cross off in mid- to late-summer. “Consistent moisture during dry periods helps them continue storing energy and developing next year's flower buds,” Kubes says. “Peonies don't like soggy soil, but prolonged drought can stress the plant and reduce the amount of flowers you will see the following spring.” By giving them a thorough soaking now, you’ll get to experience bigger, better blooms next season.
How to Water Peonies During Summer Dry Spells
In dry summer weather, your peonies need deep, consistent moisture. According to Jessica Mercer, PhD, the senior horticulturist at Plant Addicts, established in-ground varieties need one inch of water (rainwater counts!) every 10 to 14 days or whenever the top inch or two of soil is dry to the touch. Keep in mind that young and container-grown peonies dry out faster than established ones, so you might need to water those more frequently.
When soaking your perennials, aim for the roots (not the leaves, which can lead to fungal diseases) with a watering wand or porous soaking hose, advises Olivia Liebing-Slater, collections horticulturist at Matthaei Botanical Gardens & Nichols Arboretum. Sticking to an early morning watering schedule will hydrate your peonies before the hottest part of the day stresses them out, and it’ll give them enough time to dry before nighttime.
Additional Peony Summer Care Tips
While deeply watering your peonies during dry spells is an easily overlooked, incredibly important summer gardening task, there are a few other season-specific care tips to prioritize this July and August:
Keep Healthy Foliage Intact
While you can certainly cut back faded flowers, damaged stems, and diseased leaves in July and August, avoid pruning healthy green leaves in the summer, since your peonies are actively making food to store as energy for the following spring. “Removing healthy foliage during July or August can reduce the plant's energy reserves and lead to fewer or smaller blooms the following spring,” Kubes explains.
Deadhead Spent Blooms
Like we mentioned, removing spent flowers is a completely acceptable (and very beneficial) practice in the middle of summer. By cutting off faded blooms, you’ll help your peonies direct their energy toward producing food, not seeds. Snip just below the old flower, leaving the healthy foliage untouched.
Skip Heavy Fertilizing
During the dog days of summer, fertilizing your peonies can backfire. “Too much nitrogen can promote vegetative growth when the plant should be storing energy in its crown and roots for next year,” Mercer notes. Wait until the perennial’s active growing season in early spring or just after flowering to apply a balanced fertilizer.
Monitor Summer Diseases
Hot, humid summer weather can cause fungal diseases to pop up on your peonies. “While most diseases are unlikely to kill your peony, they could reduce the amount of healthy foliage collecting light and, in turn, reduce the amount of energy stored,” Liebing-Slater points out. To limit the spread of diseases and its impact on next year’s blooms, remove any infected leaves or stems as they emerge.
Manage Invasive Weeds
In July and August, especially during dry spells, your peonies need light, water, and nutrients to make food. Since summer weeds are a direct competitor to your plants’ resources, staying on top of weeding is crucial for their health.
Avoid Transplanting
Another common peony mistake that gardeners make during the summer months is transplanting or dividing their flowers. Because their vegetation is actively growing in July and August, relocating your peonies can cause root shock, water loss, and severe stress. Hold off on moving your plants until fall, which is why they’ll enter dormancy and focus on root growth, Mercer says.
By deeply water your peonies during dry spells, in addition to staying on top of deadheading, weeding, and disease management, your flowers will look better and brighter than ever come spring.
Lilly Blomquist is the associate editor at The Pioneer Woman, where she writes lifestyle stories across a wide range of topics—including news, entertainment, holidays, food, and more.
