Peonies - State by State Garden

Peony Leaves Turning Red: Causes and How to Fix It

Peony leaves that blush red or purple can look alarming. One possible cause is a fungus responsible for leaf blotch, and the damage can look far worse than it is.

Peony Leaves Turning Red: What You See

Small, round red or purple spots can appear on the upper surface of young leaves just before the peony blooms.

The spots are small and circular at first, then merge later in the season into large, glossy, irregular, dark purple blotches.
Flip a leaf over and the matching patches on the underside are tan-brown to chestnut brown.
Infection tends to be heaviest at the margins of the outer leaves.
Stems may carry purple-red flecks or streaks with soft, fuzzy edges, sometimes called red spot.
Leaves can curl or distort slightly as they keep growing.

In Colorado, healthy foliage can turn yellow or reddish-maroon in autumn.

Peony Leaves Turning Red or Something Else?

Red or purple on a peony is not always leaf blotch. Botrytis blight is another possible cause, while autumn color can be harmless.

Check the part of the plant and the time of year together before you decide anything.

Looks like	How to tell them apart
Botrytis blight	Reddish-purple leaf spots come with shriveled, discolored buds that never open, while leaf blotch leaves the buds alone.
Autumn color	In Colorado, whole leaves can turn yellow or reddish-maroon in fall, rather than showing glossy spots with brown undersides.

Botrytis paeoniae is a specific gray mold fungus that peonies are prone to. If buds are failing along with the leaf spotting, Botrytis blight is another possibility.

What Causes Peony Leaves Turning Red, and Where It Is Worst

The cause is a fungus, Graphiopsis chlorocephala, formerly named Cladosporium paeoniae. It grows on the surface of leaves, stems and leaf stalks, which is why gardeners also call the problem measles, red spot or stem spot.

Warm, humid weather gives the fungus ideal conditions; in Illinois, the disease usually appears in spring or early summer.

The reassuring part is the effect on the plant. In Illinois, early infection can look unappealing and may reduce vigor on susceptible plants, while the disease generally does not cause early leaf drop or stem dieback or significantly affect plant vitality. Spotting that appears late is usually no problem for growth.

How to Treat Peony Leaves Turning Red

Because the fungus lives on the surface and rarely harms the plant, the work is mostly cleanup and keeping foliage dry.

Confirm the symptoms by turning a leaf over, so that chestnut-brown undersides tell you it is leaf blotch rather than something that affects buds.
Check the buds for shriveling or discoloration, so that you catch Botrytis blight early if it is present.
Cut off badly spotted stems and leaves and bag them, so that fewer spores remain near the crown.
Water at the soil line in the morning, so that leaves dry quickly and stay unfavorable to the fungus.
Thin crowded stems and pull back nearby plants, so that air moves through the clump.
If you are considering a fungicide, make sure its label permits use on peonies where you live.

Do not strip the plant in a panic. Remove only what is clearly diseased and leave healthy green growth in place.

How to Prevent Peony Leaves Turning Red Coming Back

Prevention follows the season, because spores overwinter on old foliage and spread in damp weather.

Remove old leaf debris and stems from around the base so infected material does not remain near the plant.
As the plants leaf out, keep sprinklers off the foliage and water the soil instead.
Space or stake stems so air can circulate through the clump.
In Illinois, check for new spots during warm, wet weather in spring or early summer.
After the foliage has died back, cut the stems down and discard them rather than composting them.

Keep mulch away from the stems to reduce splashing onto lower leaves.

Where This Comes From

This guidance focuses on the symptoms that distinguish leaf blotch from Botrytis blight and normal autumn color. Timing and severity vary with the weather, so use the condition of your own plants to decide what needs attention.

Common Questions

Is Peony Leaf Blotch Going to Kill the Plant?

No. The fungus does not cause early leaf drop or stem dieback, and it does not significantly affect plant vitality even though the leaves look rough.

Why Do Peony Stems Have Red Spots Before the Leaves Do?

Measles-type stem symptoms typically appear before leaf blotch, and the stem lesions expand as the season goes on. Both come from the same fungus.

Can You Still Enjoy the Flowers If the Leaves Are Spotted?

Usually yes, since leaf blotch affects leaves and stems rather than buds. If buds are shriveled or discolored, suspect Botrytis blight instead.

Peony Plant Dying: Causes and How to Fix It

Brown, blotchy leaves on a peony can look alarming, and plenty of gardeners assume the plant is finished. The real question is whether the plant is losing leaves early, failing to bloom, or simply dying back on schedule.

Peony Plant Dying: What You See

Start with the stems and leaves, because the pattern of spotting tells you which disease is at work.

Distinct red to reddish-black spots on the stems, often called measles or red spot, are the sign that sets this problem apart.
Young stems show elongated, reddish-brown streaks that later turn purple as the spots merge.
Leaves carry glossy, purplish-brown circular spots on top and chestnut or milk-chocolate brown spots underneath.
Spots join into large brown or purple blotches, and leaves may twist slightly as they keep growing.
Damage tends to be heavier at the margins of the outer leaves.

Warm, humid weather favors all of this, so the spotting usually builds as the season goes on.

Peony Plant Dying or Something Else?

Several harmless or unrelated things resemble a failing peony. Look at the color and the timing together before you decide anything is wrong with the roots.

A peony that browns in autumn is simply doing what peonies do, and one that merely lacks flowers has a different list of causes altogether.

Looks like	How to tell them apart
Powdery mildew	Heavy infections can look dramatic on the leaves, yet the disease rarely kills a plant, and spotting from leaf blotch is glossy and brown instead.
Natural fall dieback	Foliage browns in autumn after a healthy summer, and the plant regrows the following spring.
Heat and drought stress	Leaves brown through much of a very hot, dry summer, and sandy soil makes the problem worse.

Gray mold is a separate fungus that also attacks peonies, while missing buds can point to growing conditions and buds that never open may signal weather, disease, insects, or poor nutrition.

What Causes Peony Plant Dying, and Where It Is Worst

Fungi are behind most of it. Leaf blotch comes from a fungus that overwinters on infected plant debris, then releases spores in spring that splash onto young foliage and stems with rain or overhead irrigation.

Warm, humid weather gives the fungus its best conditions, so wet, muggy summers produce the worst spotting. In Ohio, the measles symptoms typically appear before the leaf blotch symptoms, with the stem lesions expanding as the season progresses.

The disease looks worse than it is. Despite the ugly foliage, leaf blotch does not have a major impact on plant health and survival, so a spotted peony is usually a plant under cosmetic attack, not one at the end of its life.

In Washington, advice for peonies that fail to bloom lists too little sun, recent transplanting, planting too deep, too much fertilizer, clumps that need dividing, and cutting foliage off too early in July or August.

How to Treat Peony Plant Dying

Treatment is mostly cleanup and better watering, done in this order.

Remove infected leaves, even if that means taking all of them, so that spores have less tissue to live on.
Cut the dead stems down to the ground in late fall or early spring, before the plant breaks dormancy, so the fungus loses its winter shelter.
Bag and discard the debris instead of composting it, because spores overwinter on the old material.
Switch to drip irrigation in place of overhead sprinklers, so that the foliage stays dry and the fungus has less chance to spread.
Water sandy soil more frequently in hot, dry spells, so that drought stress does not add to the browning.
If unaffected or new leaves are emerging, a fungicide may help manage further damage.

A fungicide only helps protect leaves that are still clean, so it cannot repair tissue that is already spotted.

How to Prevent Peony Plant Dying Coming Back

Prevention follows the calendar, and most of it comes down to keeping spores and moisture away from the foliage.

In late fall or early spring, cut all dead peony stems to the ground and remove them before new growth starts.
When spring growth begins, water at the base with drip irrigation so rain-splashed spores have less help reaching young stems.
Through warm, humid summer weather, keep the leaves dry and check the stems for the first red spots.
During hot, dry spells, water sandy soil more often so the plant is not stressed on top of any disease.
In Washington, leave the foliage in place in July and August, because cutting it early can cost you buds next year.

Then expect the leaves to brown in autumn, which is normal and is no cause for alarm.

Where This Comes From

This guidance focuses on leaf blotch, natural dieback, and other problems that can look similar. Local growing conditions can change treatment timing, so match any intervention to your climate.

Common Questions

Will Leaf Blotch Kill a Peony?

Not usually. The spotting looks severe, but the disease does not have a major impact on the plant’s health or survival, and the plant regrows the next spring.

Is It Normal for Peony Leaves to Turn Brown in Fall?

Yes. Peonies die back naturally in autumn, and a plant that stayed healthy all summer needs no attention.

Why Does a Peony Have Buds That Never Open?

The listed causes include a late freeze, other extreme weather, fungal diseases, insects, and poor nutrition. Possible causes include a late freeze, other extreme weather, fungal disease, insects, and poor nutrition.

Peony Buds Not Opening: Causes and How to Fix It

Tight peony buds that brown or shrivel without unfolding are a disappointing spring sight. Possible causes include fungal blight, bad weather during bud formation, and too little sunlight. Which one it is depends on what the buds look like.

Peony Buds Not Opening: What You See

The blighted bud looks different from a healthy one in spring, when the flowers should be swelling and showing color.

Buds that turn brown or black and stay shut may have botrytis blight.
In Washington, wilting buds may carry fluffy gray mold, with brown blotches appearing on the leaves later in the season.
Young shoots discolor at the base, wilt and fall over, and stems soften and decay.
Buds stay small, tight and colorless on a plant growing in partial to heavy shade.
Little buds may die from internal rot after very rainy weather.

Where the buds sit on the plant and what the leaves look like around them tell you most of what you need to know.

Peony Buds Not Opening or Something Else?

Several problems, including fungal diseases, can leave a bud closed. Matching the bud’s look to its surroundings and the season sorts them out quickly.

Cut flowers bought for arrangements have their own version of the problem, since stems with very tight buds and no color may never open.

Looks like	How to tell them apart
Frost damage	Buds may fail to open after a late spring freeze.
Shade starvation	In Iowa, plants in partial to heavy shade may be too weak to develop their buds fully.
Botrytis blight	Buds blacken and stay shut, with gray mold on them, spotted leaves and soft stems, most often after cool, rainy weather.

Extra fertilizer, a clump that needs dividing, and insect damage can also keep buds from opening.

What Causes Peony Buds Not Opening, and Where It Is Worst

The fungus Botrytis paeoniae attacks stems, leaves and flower buds, and it is most common in cool, rainy weather. It also thrives in dark, moist places, and infections often show up behind the buds just before they open.

Weather without disease can do the same damage. Buds formed during very rainy weather may rot inside, because the plant missed its window at a critical point in bud development. Possible causes also include late freezes, other extreme weather, fungal diseases, insects and poor nutrition.

Shade is the quiet cause. Peonies bloom best in full sun, and in partial to heavy shade the plants are weak and cannot feed the developing buds, so the undernourished buds do not develop fully. Botrytis blight is most common in cool, rainy weather.

How to Treat Peony Buds Not Opening

Sanitation is the most effective way to deal with blight, so most of the work is cleanup, followed by a look at light and feeding.

Check the leaves and the base of the shoots for spots, soft stems and discolored tissue to confirm whether blight is behind the trouble.
Partial to heavy shade can leave peonies too weak to develop buds fully.
In Iowa, move peonies growing in partial to heavy shade to a sunny site in September.
If a plant was fertilized more than its neighbors, extra feeding may be part of the problem.

A clump that needs dividing may also produce buds that fail to open.

How to Prevent Peony Buds Not Opening Coming Back

Prevention follows the year, with the biggest job in fall and the rest being watchfulness in spring.

In Indiana, start controlling blight with a thorough fall cleanup of old, infected stems, leaves and other plant debris.
In Iowa, check young shoots for discolored bases, wilting, or stems that fall over.
Cool, rainy spring weather favors botrytis, so watch buds and leaves for symptoms.
Skip cut stems with very tight buds and no color; also check for gray mold before buying.

Full sun supports bloom, and fall cleanup helps control blight.

Where This Comes From

These details are based on plant-health guidance. Check what suits your local weather and soil.

Common Questions

Can Peony Buds That Turned Black Still Open?

No. Buds that blacken and fail to open will not bloom.

Why Do Peony Buds Fail to Open After a Rainy Spring?

Very rainy weather can cause internal rot in small buds while they are forming. Wet springs also favor botrytis, which blackens buds and keeps them closed.

Is It Safe to Compost Diseased Peony Stems?

Remove old, infected stems, leaves and other plant debris in fall.

Peony Leaves Turning Brown: Causes and How to Fix It

In Illinois, small spots may appear just before bloom and merge into large blotches later in the season. A fungus causes it, and the disease looks worse than it acts. The plant itself usually keeps growing, so the real question is how to tell this problem from its lookalikes and how to keep the leaves tidy.

Peony Leaves Turning Brown: What You See

Start with the color and the sheen, because the disease has a very particular look on the two sides of the leaf.

The top of the leaf shows glossy, purplish-brown spots, often circular at first.
Flip the leaf over and the same spots turn a chestnut or milk chocolate brown.
Small spots merge into large, irregular blotches as the season goes on.
The outer leaves, especially along their margins, tend to show more damage.
Young stems can carry raised spots that join into short, reddish-brown to purple streaks.

In Illinois, spots on young leaves may appear just before bloom; in Ohio, stem lesions usually appear first and lengthen as the season progresses.

Peony Leaves Turning Brown or Something Else?

Several peony problems share a few symptoms with leaf blotch. Checking the surface of the leaf and the spot on the plant keeps you from treating the wrong thing.

Both gray mold and powdery mildew are real lookalikes, and each leaves a distinct signature once you know where to look.

Looks like	How to tell them apart
Powdery mildew	Starts as small white spots that spread into a white-to-gray powdery coating over the whole leaf, which leaf blotch never produces.
Gray mold (Botrytis)	Brown or purplish-brown circular spots, sometimes followed by brown, rotting buds.
Leaf blotch	Glossy purplish-brown spots on top, chestnut-brown underneath, with reddish stem streaks.

Phytophthora blight also deserves a look if a shoot collapses or the base of the plant is affected. Black lesions several inches long on young shoots, along with browning at the base of leaves, point toward that problem and away from simple leaf blotch.

What Causes Peony Leaves Turning Brown, and Where It Is Worst

The usual cause is a fungus, Graphiopsis chlorocephala, formerly called Cladosporium paeoniae. The same disease goes by leaf blotch, measles, or stem spot, and it spreads when the weather is warm and humid.

No single region owns this disease. It shows up wherever summers turn muggy, and in Illinois, leaf blotch and powdery mildew appear fairly regularly on peonies during the summer months.

Timing matters for how much to worry. In Illinois, early infection can look unappealing and may reduce plant vitality, while infection that appears late in the season is usually not a problem for growth. Despite the dramatic look, leaf blotch does not significantly affect plant vitality.

How to Treat Peony Leaves Turning Brown

Start by confirming leaf blotch from its distinctive spots and streaks.

Confirm the diagnosis by checking the underside of the leaf and the stems, so that you treat leaf blotch and not mildew or a blight.

A collapsed shoot, suddenly rotting buds, or an affected crown points to a different problem.

How to Prevent Peony Leaves Turning Brown Coming Back

Watch for the glossy spots and reddish stem streaks that identify leaf blotch.

Where This Comes From

These symptoms and causes are based on plant-disease guidance. Check local guidance for timing and treatment rules.

Common Questions

Should You Cut Back Peonies with Brown Leaves?

Can Brown Spots on Peony Leaves Kill the Plant?

Leaf blotch does not significantly affect plant vitality, so the plant usually survives. A collapsing shoot or a rotting crown is a different situation and calls for a closer look.

Why Are Peony Buds Turning Brown and Rotting?

Brown, rotting buds point to a blight rather than leaf blotch. Botrytis is more likely than Phytophthora to cause bud rot, and both can turn buds brown suddenly at any stage of development.

Peony Buds Turning Black: Causes and How to Fix It

Open a peony bud and find it dark, shriveled and dry instead of swelling toward a bloom, and a common culprit is botrytis blight. It lives on last year’s leftover foliage and spreads in damp weather. Cleanup does most of the work of limiting it.

Peony Buds Turning Black: What You See

The clearest sign is the bud itself, though the same fungus leaves marks elsewhere on the plant.

Flower buds turn black to brown and never open, and small ones often dry up while larger ones turn brown and may wear a brown spore mass.
Sometimes the bud is the only part of the plant affected, so the foliage can look perfectly healthy beside a ruined bud.
In wet weather, fluffy gray spores show up on infected parts, which is the mark of gray mold.
Stems develop brown or black patches, often with a target-like spot, and cutting into a wilted stem can reveal a brown or blackish rot at its base.
In Minnesota, new shoots turn black, wilt and die as they emerge in spring, and leaves and petals get black to brown irregular spots.

In Texas, young shoots at any stage, buds included, may suddenly wilt and fall over.

Peony Buds Turning Black or Something Else?

Several peony troubles darken tissue, and they call for different handling. Dark buds alone do not settle it, so check what else is happening on the plant and where the dark tissue sits.

Gray mold also has a simple home test. Sealing a piece of diseased tissue in a plastic bag with moistened paper towels coaxes the mold out and makes the diagnosis much easier.

Looks like	How to tell them apart
Phytophthora blight	Dark brown or black patches turn leathery on stems, leaves and buds, and black lesions several inches long may sit at the base of the stem, causing wilting and death.
Leaf blotch (red spot or measles)	Small red spots and blotches show on leaves and stems, and the fungus returns most years once it has appeared in the bed.
Bud blast from other causes	Aborted buds fail to open, but botrytis is only one of several possible reasons, so look for gray spores or stem rot before blaming it.

Botrytis is more likely than phytophthora to cause bud rot, which helps when the buds are the only thing affected.

What Causes Peony Buds Turning Black, and Where It Is Worst

The fungus Botrytis paeoniae, called peony blight, early blight or bud blast, is the usual cause. It overwinters on the surface of decayed peony foliage, and spores later spread by wind, splashing rain or dirty tools.

Wet, rainy conditions that leave free moisture on the plant favor it, as does injured tissue. Cool, rainy weather favors the disease in Texas, while wet weather favors it in California. The fungus also survives on plant debris and as small resting bodies in or on the soil.

It follows wet springs and untidy beds, which means cool, damp seasons can bring it on.

How to Treat Peony Buds Turning Black

Treatment is mostly cleanup, since fungicides help only a little against this disease.

Remove infected plant material promptly so it cannot produce more spores.
Remove spent blooms promptly, because good sanitation greatly reduces botrytis problems.
Keep pruners clean, since spores can travel on tools.
Consider a fungicide early in the season, when shoots are about six inches tall, because it can help protect the plant at that stage, and spray all parts to wet foliage and soil thoroughly.

Fungicides have limited effectiveness against botrytis.

How to Prevent Peony Buds Turning Black Coming Back

Because the fungus survives on old growth and in the soil, prevention follows the calendar from fall cleanup through spring.

In California, remove or burn old growth in fall so spores have no leftover foliage to overwinter on.
Cut stalks below ground level.
In Minnesota, check emerging shoots in spring for blackening or wilting.
When shoots reach about six inches tall, apply a protective spray.
Through bud and bloom season, clip spent blooms promptly and clear debris from around the crowns, especially after rainy spells.

Leaving old foliage in place invites the problem back.

Where This Comes From

These notes are based on plant-disease guidance. Confirm timing and approved products locally before you act.

Common Questions

Will Peony Buds Turning Black Kill the Plant?

Sometimes only the buds are affected. Black lesions at the base of the stem can cause wilting and death, so stem damage is the more serious sign.

Can You Still Get Blooms After Some Buds Turn Black?

Buds that have gone black will not open.

Should You Cut Peonies Back After Botrytis?

Yes. Cut stalks below ground level; in California, remove or burn old growth in fall.

Thrips on Peonies: How to Spot Them and Get Rid of Them

Peony buds swell to a good size in spring, then stay shut or open into lopsided, half-formed flowers. Tiny insects hiding inside the bud are often the cause. Thrips are small enough to miss with a quick look, so the trick is knowing where they hide and what their damage looks like on the plant.

Thrips: What You See

The insect itself is hard to spot, so most gardeners recognize the damage first and then go looking for the culprit.

The insects are slender and flat with fringed wings, and most adults are under ¹/20-inch long, with colors ranging from light yellow to black.
They tuck into flower buds, leaf folds and other tight crevices, which is why a glance at the open foliage often shows nothing.
Inside an opened bloom, look at the thick base of the inner side of the petals, where they tend to gather.
Buds grow large but only a handful open, and the few blooms that do open are not fully formed, often with one side left underdeveloped.
Petals and tissue show discoloration, distortion and dead patches where the insects punctured the surface and sucked out the sap.

Egg laying can scar the tissue as well, so damage does not always come from feeding alone.

Thrips or Something Else?

Lopsided blooms and stalled buds can have different causes, and treating the wrong problem leaves the real problem unaddressed. Pull a bud apart and look for the tiny, slender insects inside.

Check the whole plant, not only the bud, before deciding.

Looks like	How to tell them apart
Bud blight from gray mold fungus: buds that turn brown or black and never open	Fungus leaves fuzzy gray growth on the bud or stem and rots the tissue, while thrips leave dry, distorted patches and tiny moving insects inside the bud.
Late frost injury: blackened buds or twisted, damaged new shoots	Frost hits many buds and shoots at the same time after a cold night, while thrips damage builds bud by bud and shows insects when the bud is opened.

Ants crawling over the buds often cause worry, but they are there for the sweet sap the buds produce. Ants on the surface with no distortion underneath point away from thrips.

What Causes Thrips, and Where It Is Worst

Thrips spend the winter mostly at the edges of fields, with fewer inside them, so beds that sit beside tall grass, weedy borders or field margins get visited first. In spring they move in. They are mobile enough to find your peonies from a neighbor’s yard, and the color of the flower or the presence of pollen does not steer where they settle first.

A tight, young bud keeps them out, but they lay eggs on the outside of the bud in protected spots. The immature thrips slip into the bloom as the bud opens, and they feed there as the flower develops.

How many generations you face depends on how warm your growing season is. In Alaska, Southcentral farms will likely see two generations and a partial third during the peony season, while Interior farms will see one and a partial second. Outside Alaska, inspect plants rather than assuming a regional pattern.

Thrips can also carry plant viruses to other plants, which makes them a bigger concern than the sap they drink.

How to Treat Thrips

Treatment starts with removing what you can reach by hand and ends with getting local advice on anything sprayed.

Inspect the buds and the base of the petals closely, so that you know thrips are the problem before you act.
Cut off damaged buds and distorted blooms, so that the insects and eggs inside them are removed from the plant.
Seal the cuttings in a bag and put them in the trash, because tossing them on the compost pile or the ground lets the insects crawl back to your plants.
Clear weeds and old plant debris around the bed, so that the sheltered edges where thrips overwinter and hide are gone.
Before applying a treatment, read the label and local rules carefully to make sure it is legal and labeled for peonies.

Established peonies are unlikely to die quickly if you do nothing, but the number of buds and blooms drops markedly, which is the real cost of ignoring thrips. Neighboring plants can be at risk of virus spread too, so acting early protects more than the peonies alone.

How to Prevent Thrips Coming Back

Prevention follows the season, and most of it is housekeeping near the bed.

In early spring, clear dead leaves, old stems and weeds from the bed and from the edges around it, where thrips spend the winter.
As the buds form, look inside a few of them and along the leaf folds regularly, so that you catch the first insects before they spread.
During bloom, remove any bud that looks stunted or lopsided right away and bag it, because the insects inside will move on to the next flower.
After the season ends, remove and bag dead stems and loose debris.

Keep the grass and weeds around the bed trimmed through the growing season, since thrips favor the margins before they move into the planting.

Where This Comes From

The Sources box below lists the references behind these details on thrips and peonies. Local rules and product labels determine which treatments may be used in your area.

Common Questions

Will Thrips Kill an Established Peony?

Not quickly. An established plant is unlikely to die from thrips, but it will produce far fewer buds and blooms until the problem is dealt with.

Do Thrips Prefer Certain Flower Colors?

No. Where thrips first settle does not depend on flower color or on whether there is pollen, so every color is a possible target.

Can Thrips Get Inside a Closed Bud?

Not in a very young one. Even though they are minute and flat, thrips cannot penetrate a stage 1 bud. They lay eggs on the outside in protected spots, and the young enter as the bud opens.

Scale on Peonies: How to Spot Them and Get Rid of Them

Small, hard bumps on a peony stem, sometimes with ants climbing up and down them, usually mean scale. The insect settles on the bark and stays put, so it is easy to overlook until you run a hand along the stems. Peony scale is a small armored insect that blends into the wood, and it can be found and dealt with once you know what to look for.

Scale: What You See

The signs are small and easy to mistake for part of the stem, so look closely at the bark.

Small round white discs stay stuck to the stems long after the insect itself has fallen away.
Live scales are small, purple, round or oval, and about 3/32 inch across, covered by a grayish-brown armor that matches the bark.
Each one sits as a little raised bump, convex like a tiny dome.
Some burrow so far into the bark that they are nearly hidden.
Newly hatched crawlers are tiny, flat, and purple.
Clear, sugary honeydew may coat the stems, and ants come to feed on it.

Heavy infestations weaken the plant, so a stem crusted with bumps deserves attention.

Scale or Something Else?

Several common problems can look like scale at a glance. A closer look at where the spots sit and how they behave sorts them out quickly.

Run a fingernail over a suspect bump. Scale armor sits on the stem like a small cap, while other look-alikes are part of the plant or move around.

Looks like	How to tell them apart
Lichen: crusty gray-green patches on older woody stems	Flat and spread out rather than domed, and it shows up as irregular patches instead of scattered, evenly sized bumps
Aphids: clusters on new shoots and buds, with ants nearby	Soft bodies that crowd together on tender growth and move when touched, while scale stays fixed in place on harder bark
Natural bark roughness: small pale bumps on woody stems	Part of the stem and the same color as it, with no purple body or white disc underneath when you scrape gently

Sticky stems with ants alone do not settle the question. Honeydew comes from aphids and other sap feeders too, so look for the armored bumps themselves before you treat.

What Causes Scale, and Where It Is Worst

Scale arrives as crawlers, the tiny flat purple stage that wanders briefly across a stem. Once a crawler finds a spot it likes, it picks a permanent feeding site and stays there. It feeds by piercing the stem and drawing out sap through sucking mouthparts.

Females lay their eggs under their own armor, so an overlooked patch can restock a stem. Large populations can weaken the plant.

Peony scale is worth checking for when a peony develops raised bumps on its stems. Crowded plants with little air movement and stems that never get a close inspection give it the easiest start.

How to Treat Scale

Start by cutting down the numbers physically, then bring in a treatment your state approves.

Inspect every stem with good light and a hand lens if you have one, so that you know how far the infestation reaches before you cut or spray.
Scrub light infestations off the stems with a soft brush or a fingernail, so that the insects and their armor are removed instead of left to hatch more crawlers.
Remove loose scale and bag the debris, but do not cut a woody stem at the base simply because scale is present.
Before using a treatment, read the label and local rules carefully, so that anything you apply is legal and labeled for peonies.
Time any treatment for when crawlers are active, because the tiny flat purple stage is easier to reach than an adult hidden under its armor.
Check the stems again soon after, so that survivors or fresh crawlers get caught before they settle in.

Armor often stays on the stem after the insect dies, so a white disc alone does not mean the scale is still alive. Look for the purple body under a lifted armor before repeating a treatment.

How to Prevent Scale Coming Back

Prevention for scale means a regular look at the stems through the growing season, since the insects settle in quietly.

Check new growth and the base of the clump as stems emerge, so that any leftover crawlers are caught before they settle.
Watch for ants moving up and down the stems, because they often point to honeydew and the insects producing it.
Look for white discs and raised bumps on the stems, where the armor tends to stay behind.
When dead herbaceous stems are cut back, bag and discard the cuttings instead of composting them, so that eggs under old armor do not carry over.
Before growth restarts, scan any woody stems and scrub off whatever you find.

Spacing plants so air moves through the clump makes every one of these checks easier.

Where This Comes From

The Sources box below lists the references behind these descriptions and life-cycle details. Local rules and product labels determine what may be used where you live.

Common Questions

Will Scale Kill a Peony?

Scale feeds on sap, and a heavy infestation weakens the plant over time. A small number on a few stems is a nuisance that you can usually manage by scrubbing and cutting out the worst stems.

Who Can Confirm That It Is Scale?

A knowledgeable local gardener can look at a cut stem and help identify the bumps. Bring a piece with the bumps and any sticky residue still on it.

Can Scale Spread to Other Plants in the Yard?

Crawlers move short distances before settling, so shrubs close to an infested peony are worth a look. Check nearby woody plants for the same raised bumps and white discs before assuming they are clear.

Root-Knot Nematodes on Peonies: How to Spot Them and Get Rid of Them

Peonies that stay small and weak and produce no flowers may be showing that something is wrong underneath the soil. Root-knot nematodes, tiny worms that feed inside the roots, can cause these symptoms. Confirming them takes a look at the roots, and getting rid of them means treating the plant itself and moving it.

Root-Knot Nematodes: What You See

The signs show up on the whole plant and then on the roots, so look at both when a peony is struggling.

Fine roots carry round swellings called galls, each about one-eighth inch in diameter.
The root system looks short and stubby instead of long and branching.
Sliced through, a gall shows brown areas packed with small round worms, also called eelworms.
The plant stays small and weak compared with healthy peonies nearby.
No flowers form, even on a clump that is old enough to bloom.

The galls are the sign that sets this problem apart, so dig gently at the edge of the clump and wash some fine roots to see them clearly.

Root-Knot Nematodes or Something Else?

A peony that sulks without blooming has many possible causes, and a poor plant above ground proves nothing by itself. The roots decide the question.

Nodules and swellings also turn up on other plants, so check the shape and the inside of the swelling before you decide.

Looks like	How to tell them apart
Small, weak plant that never flowers	Dig a few roots. Nematode damage shows galls on the fine roots, and a slice through one reveals brown areas full of worms.
Short, stubby roots	Look at the fine roots for galls about one-eighth inch across. Stubby roots with no galls point to another cause.

Poor planting, too much shade or a clump set too deep can also keep peonies from blooming, but they do not produce galls with worms inside. If you cannot tell, have a sample of roots and soil analyzed.

What Causes Root-Knot Nematodes, and Where It Is Worst

The cause is the nematode itself, a small round worm that lives in soil and feeds on peony roots. It enters the fine roots, and the galls are the swellings that form where it feeds. The damage cuts the plant’s ability to take up water and nutrients, which explains the small size and the missing flowers.

The worms travel in soil, and a division or root bought from an infested bed carries them into a new spot. That is how a healthy garden picks up the problem.

Soil that has already held infested plants is the place to be most careful.

How to Treat Root-Knot Nematodes

Treatment means cleaning the roots and crown, then planting them somewhere new, in this order.

Dig the whole clump carefully, so that you keep the roots and crown intact for treatment.
Wash the soil off, so that you can see the galls and judge how far the damage goes.
Soak the roots and crown in hot water at 115 F for one-half hour, because that heat kills the nematodes in the tissue.
Choose a new planting spot away from the old one, so that the survivors left in the soil cannot reach the clean roots.
Plant the heat-treated roots there, which prevents reinfestation.

Keep the water steady at that temperature, since too hot harms the plant and too cool will not kill the worms. Check whether any soil treatment is approved where you live, because that varies by state.

How to Prevent Root-Knot Nematodes Coming Back

Prevention follows the planting calendar, and it starts with where the roots come from.

Check new peonies and any divisions you plan to plant for galls on the fine roots before they go into the ground.
Watch for small, weak plants that fail to put up strong stems.
Keep tools and boots clean when moving between beds, so soil from a sick clump does not travel to a healthy one.
Set heat-treated roots in a new location rather than back into the old hole.
If a plant remains weak, lift it and look at the roots instead of waiting for flowers that never come.

A laboratory analysis of soil and roots can confirm the diagnosis before you replant.

Where This Comes From

Rules and options differ by state, so check local rules before you treat or replant.

Common Questions

Can You Save a Peony with Nematodes?

Yes, in many cases. Hot-water treatment of roots and crown at 115 F for one-half hour kills the nematodes, and planting the treated roots in a new location prevents reinfestation.

Why Is My Peony Small and Not Blooming?

A weak plant with no flowers can be a sign of nematodes, but confirm it by checking the roots for galls and short, stubby growth. Without galls, look at planting depth, light and other causes.

Should You Replant in the Same Spot?

No. Plant the treated roots in a new location, since the soil of the old spot can still hold worms that would infest the clean roots again.

Rabbits on Peonies: How to Spot Them and Get Rid of Them

Chewed stems in spring and ants crawling over the buds a little later are very different problems on the same plant. Rabbits are a matter of clipped shoots and protection. The ants turn out to be harmless visitors. Telling them apart saves you from treating the wrong thing.

Rabbits: What You See

Rabbit damage on a peony shows up in the plant itself and on the ground around it, usually in spring when the shoots are young and tender.

Young stems are cut off cleanly at a slanted angle, as if with small pruning shears, and the cut ends look fresh and pale.
Round, firm droppings lie scattered in the mulch or on the lawn edge near the clump.
Shoots that were growing yesterday are simply gone, leaving short stubs rather than torn or shredded stalks.
Soft fur tufts or shallow scratched patches sometimes show in the bed where a rabbit rested or dug.
Damage tends to sit low on the plant, within easy reach of an animal standing on the ground.

A clump with clipped shoots and droppings nearby points to a rabbit, and the damage often repeats until the plant is protected.

Rabbits or Something Else?

Many gardeners see movement on their peonies and assume something is feeding on them. Often it is ants on the swelling buds, which is normal and not a sign of rabbit trouble.

Deer are the other animal that gets mistaken for rabbits, and they leave a different mark. Their bites look ragged and torn, and they reach higher up the plant than a rabbit can.

Looks like	How to tell them apart
Ants crawling over closed peony buds, as if something were feeding on the plant	The stems are intact and the buds are whole. The ants visit the nectar glands on the outside of the buds and leave once the bloom is complete.
Rabbit clipping, with shoots missing from the clump	Stems end in a clean slanted cut and round droppings lie nearby. Nothing crawls on the buds.

Ants and rabbits can show up in the same bed in the same season, so check the stems for cuts and the ground for droppings before deciding what you are dealing with.

What Causes Rabbits, and Where It Is Worst

Rabbits come for soft, fresh growth. Peony shoots push up early in the season when little else in the yard is green, and nearby cover can make the clump easy for rabbits to approach.

Beds close to shelter give rabbits an easy, quiet approach.

The ants are a separate matter. Peony flowers feed them, and in return the ants guard the blossoms from other insects that feed on flowers. Gardeners call that give and take mutualism, and it is why a bud covered in ants is no cause for alarm.

How to Treat Rabbits

Start by confirming the animal, then block its access, because a barrier works where chasing does not.

Check the stems for slanted cuts and the soil for droppings, so that you treat rabbits only when the signs are really there.
Leave the ants alone, since they are doing the plant a favor and will leave by themselves after bloom.
Surround the clump with wire mesh fencing, set snugly against the ground and staked firmly, so that a rabbit cannot slip underneath or push through.
Clear brush, woodpiles and tall weeds near the bed, so that the animals lose the cover they use to approach unseen.
Replace chewed or leaning guards as the shoots grow, so that fresh growth never ends up outside the barrier.
Check which repellents and control methods are approved where you live, so that you stay within local rules.

Cut stems will not regrow from the clipped point, so protect the clump early.

How to Prevent Rabbits Coming Back

Prevention for peonies follows the plant’s own year, since the vulnerable moments are the first shoots and the quiet weeks after flowering.

In early spring, set the fence around the clump before the red shoots break the soil, so the first growth is never exposed.
While the buds swell and open, let the ants work and keep the fence in place, since both visitors can be around at once.
Once the bloom is complete, the ants will move on; remove spent flowers for a tidy bed and keep the fence in place.
In summer, mow the lawn edge beside the bed regularly and trim back tall grass, so that rabbits find no cover on the approach.
After the foliage dies back, cut it down and clear leaf litter from the base of the plant.

A tidy bed and a secure fence make the plants less inviting and harder to reach.

Common Questions

Do Peonies Need Ants to Bloom?

No, that is a myth. Peonies bloom without ants, and the ants simply benefit from the nectar while the flowers benefit from their guard duty.

How Can You Tell Rabbit Damage from Deer Damage?

Look at the bite and its height. Rabbits leave a clean slanted cut low on the stem, while deer leave torn, ragged ends and can reach much higher.

Should You Wash Ants Off Peony Buds Before Cutting Flowers?

You do not need to treat the plant. If you bring cut flowers indoors, a gentle shake outside is enough, and any ants left on the buds will wander off on their own.

Where This Comes From

Control rules vary by area, so confirm local rules before choosing a method.

Japanese Beetles on Peonies: How to Spot Them and Get Rid of Them

Metallic green beetles clustered on an open peony bloom, and leaves that look like lace by midsummer, point to Japanese beetles. They arrive after the main peony show is nearly over, but they find the last blooms and the foliage anyway. Handling them well comes down to knowing what they look like, what they are not, and when they feed.

Japanese Beetles: What You See

The damage is usually easier to spot than the beetle, so start with the leaves and blooms.

Leaves turn lacelike, because the adults eat the tissue between the leaf veins and leave the veins standing.
Beetles sit on open blossoms, since rose and peony blooms are especially susceptible.
Flower buds get chewed too, and the adults also go after fruits, including overripe and decaying ones.
Beetles gather on low plants early in the day, where they crawl up to warm their bodies before taking flight.
In New Hampshire, adults emerge from the soil between the last week of June and early July, and feeding peaks from mid-July through August.

In New Hampshire, beetles may stay around until the first frosts of early fall.

Japanese Beetles or Something Else?

Chewed peony foliage is not always the work of this beetle. Judge by the pattern of the damage and by the place and time you find the culprit, not by a single hole or a single insect.

The leaf pattern matters most. Lace with the veins left intact on leaves, along with beetles on open flowers, fits the beetle.

Looks like	How to tell them apart
Disease spotting on leaves	Spots and blotches leave the leaf tissue whole and show no insects on the plant. Beetle damage removes tissue between the veins and the beetles are in plain sight on the leaves and blooms.
Bud damage from other chewing pests	Look at the buds and the foliage together. Beetles feed on both and leave lacy leaves, while a bud problem alone with clean foliage points elsewhere.

Disease is a separate matter from beetles, and cultivar choice affects it. Among the cultivars tested, Festiva Maxima and Bowl of Beauty are less susceptible to disease, but that says nothing about beetle feeding.

What Causes Japanese Beetles, and Where It Is Worst

The adults come up out of the soil each summer, feed on the plants around them, and the cycle repeats. Those that emerge near your peonies find blossoms, buds and foliage within easy crawling distance.

Timing varies by place. In New Hampshire, adults emerge from the soil between the last week of June and early July and are most active from mid-July through August. Confirm local timing before planning control.

Peonies are also a favorite of the Tiphia wasp, which preys on beetle grubs. In that research, peonies were the most attractive ornamental tested as a nectar source and were not susceptible to Japanese beetle feeding; peony blossoms can still be susceptible. They help as one part of the solution, not the whole answer.

How to Treat Japanese Beetles

Work in this order, starting as soon as you see the first beetles on the plants.

Check the plants early in the day, when beetles are sluggish and still warming up on low growth, so you can find them and reach them easily.
Knock or pick the beetles into a container of soapy water, which removes them before they draw more beetles to the same blooms.
Remove or cut off badly chewed blooms and buds, so the plant does not keep attracting more feeders.
Clear overripe or decaying fruit from beneath and near the bed, since adults feed on it too.
Check which products are approved where you live, because registrations differ from state to state.

Keep checking regularly through the peak weeks, because new adults keep arriving while the season runs.

How to Prevent Japanese Beetles Coming Back

Prevention follows the beetle’s year, and most of it happens before the adults show up.

In early summer, before adults emerge, plan to watch the beds, since the first emergence falls between the last week of June and early July in New Hampshire.
In New Hampshire, check peony foliage and any remaining blooms regularly from mid-July through August, when feeding is heaviest.
In New Hampshire, keep an eye out for stragglers in early fall, since beetles can linger until the first frosts.
Through the growing season, keep peonies in the garden to feed Tiphia wasps, which prey on the grubs, though this is only part of the answer.

Pick up fallen fruit and spent blooms as you go, so the beds stay less attractive to feeding adults.

Where This Comes From

Timing and treatment rules differ by state, so check local rules before you act.

Common Questions

Do Japanese Beetles Kill Peonies?

They damage leaves, buds and blooms, but those signs alone do not show that the plant is dying. That harms the plant’s look and its flowering. Peonies are susceptible to blossom feeding, so protect the blooms you want to keep.

Are Peonies Good for Beneficial Wasps?

Yes. Peonies provide nectar for the Tiphia wasp, which preys on Japanese beetle grubs. Planting them is one part of the solution, not a cure for every beetle problem.

When Do Japanese Beetles Show Up?

In New Hampshire, adults emerge between the last week of June and early July. Activity peaks from mid-July through August, and some may remain until the first frosts of early fall. Timing in your state may differ.