The anemone genus covers a huge range of garden plants, from tiny spring-flowering corms like Anemone blanda and the florist's A. coronaria to the tall, long-flowering Japanese anemone that lights up autumn borders. Each group has slightly different vulnerabilities, but they share the same handful of problems that cause leaves to curl, distort, or deteriorate. Powdery mildew and aphids top the list for most species, while Japanese anemone has an additional weakness for vine weevil damage.
1. Powdery mildew
Powdery mildew is the most common disease of Japanese anemone (Anemone x hybrida and allies) and frequently ruins the foliage as plants reach their late-summer flowering peak. The fungal pathogens, including Erysiphe species, colonize leaf surfaces and cause a dusty white or grey coating. Affected leaves curl or pucker upward around infected patches. Anemone grown in sheltered positions with dense surrounding planting, where air circulation is restricted, suffer most severely.
What to look for
- White or grey powdery coating on upper leaf surfaces
- Leaves curling or puckering upward around infected areas
- Symptoms spreading from the most sheltered or shaded stems outward
- New growth distorted or stunted in severe outbreaks
- Worse in warm, dry weather following humid conditions
How to fix it
Remove and bin all heavily infected leaves. Thin surrounding plantings and cut back competing vegetation to improve airflow. Apply a sulfur-based or potassium bicarbonate fungicide every seven to ten days during active infection. Avoid overhead watering. After flowering, cut Japanese anemone stems back to basal level to remove infected growth and allow a flush of clean new foliage. Do not compost infected material.
2. Aphids
Aphids colonize anemone at various times: spring species are targeted when tender corm-grown leaves first emerge, while Japanese anemone is most vulnerable on its new growth in late spring and early summer before it hardens off. Colonies concentrate on stem tips and young leaf undersides, extracting sap and causing leaves to cup and curl around the feeding clusters. Anemone aphid (Aphis gossypii) and green peach aphid (Myzus persicae) are both recorded on anemone.
What to look for
- Tightly curled or cupped leaves at shoot tips and on new growth
- Pale green, yellow, or black insects clustered on stems and leaf undersides
- Sticky honeydew residue on foliage and nearby surfaces
- Ants tending colonies on stems
- Sooty mold on honeydew in persistent infestations
How to fix it
Blast aphids off with a strong jet of water. Apply insecticidal soap or neem oil every three to five days until colonies are eliminated. Check weekly during the main spring flush of new growth. Encourage natural predators. For spring anemone grown in containers, inspect weekly from the moment shoots emerge as colonies can become established before flowering begins.
3. Vine weevil
Vine weevil is a significant pest of Japanese anemone, particularly plants grown in containers or in beds with a history of the pest. Adult weevils cut U-shaped notches in leaf margins at night. The larvae, white C-shaped grubs in the soil, eat anemone roots from late summer through autumn, causing plants to wilt, curl, and collapse suddenly even when soil moisture is adequate. Container plants are at higher risk than open-ground specimens because the confined root zone is easily overwhelmed by a small grub population.
What to look for
- U-shaped or scalloped notches cut into leaf margins (adult feeding)
- Plants wilting and showing leaf curl despite moist soil in late summer
- Plant rocking loosely in the ground with little root resistance
- White, legless, C-shaped grubs with a brown head found in soil when lifted
- Adults discovered under pots, debris, or bark when checked at night
How to fix it
Apply biological control nematodes (Steinernema kraussei) to moist soil from late summer when soil is above 5 C. This targets larvae before they grow large enough to cause serious damage. Water nematodes in thoroughly and keep soil moist for two weeks after treatment. Check under pots at night for adults. In areas with persistent vine weevil problems, apply nematodes preventatively each year in late summer as a routine measure.
4. Drought stress
Anemone, especially the tall Japanese species, prefers consistently moist but well-drained soil. In full sun or during dry spells, particularly on sandy or gravelly soils, the leaves roll inward along their midrib to reduce the surface area exposed to sun and wind. This drought-induced curl is reversible and the plant recovers quickly after deep watering. Persistent drought stress reduces flowering and can weaken the plant enough to make it more susceptible to pests and disease.
What to look for
- Leaves rolling inward lengthwise, looking dull or glaucous
- Soil dry at depth when probed with a finger
- Leaves recovering and flattening after watering or rain
- Whole plant drooping slightly in the heat of the day
- Flowering reduced or stems shorter than in previous seasons
How to fix it
Water deeply at the base of the plant during dry spells, ensuring moisture reaches the root zone. Apply a 5 to 8 cm layer of organic mulch around the plant to conserve moisture and regulate soil temperature. Japanese anemone in full sun is much more drought-prone than the same plant in partial shade: if drought stress is recurring, consider moving the plant to a shadier position.
5. Rust
Anemone rust caused by Puccinia recondita and related species occasionally affects garden anemones, producing orange to rust-brown spore masses on leaf undersides. The corresponding upper surface shows pale yellow spots or streaks. Infected leaves curl and may drop early, weakening the plant. Rust is most common in cool, moist conditions in spring and autumn and spreads rapidly by windborne spores.
What to look for
- Orange to rust-brown powdery pustules on leaf undersides
- Pale yellow or chlorotic spots on the upper leaf surface above pustules
- Leaves curling inward around infected areas
- Orange powder rubbing off on fingers when undersides are touched
- Infection spreading from lower or older leaves upward
How to fix it
Remove and bin all infected leaves immediately. Apply a copper-based fungicide or a systemic product containing tebuconazole every ten to fourteen days during active infection. Clear all plant debris at the end of the season. Improve airflow around plants and avoid overhead watering, which spreads spores.
6. Cold damage
Spring anemones (A. blanda, A. nemorosa, A. coronaria) emerge early and are vulnerable to late frosts. Cold-damaged leaves develop water-soaked or translucent patches that curl, turn brown, and die as the temperature rises. Japanese anemone is more frost-tolerant but its emerging growth in late spring can be caught by unexpected cold snaps, causing similar damage to the most exposed new leaves.
What to look for
- Leaves curling and developing water-soaked or translucent areas after a cold night
- Damage turning brown and papery as temperatures recover
- Young growth at stem tips most severely affected
- Symptoms appearing suddenly after a late frost rather than developing gradually
- Crown remaining firm and producing new undamaged growth within weeks
How to fix it
Cover tender spring anemones with horticultural fleece on nights when frost is forecast. For established Japanese anemone, late cold damage to emerging growth is rarely fatal: leave it in place and new healthy growth will follow. Cut back damaged stems once growth confirms recovery. In very cold gardens, protect the crowns of tender anemone species with dry mulch from late autumn.
Quick diagnosis checklist
| Symptom | Most likely cause | First action |
|---|---|---|
| White powder, upward curl, late summer | Powdery mildew | Remove leaves, sulfur fungicide, improve airflow |
| Curled tips, insects on stems, sticky residue | Aphids | Water blast, insecticidal soap |
| Notched margins, wilt with moist soil, grubs at roots | Vine weevil | Nematode drench late summer |
| Inward roll, dry soil, recovers after watering | Drought stress | Deep water, mulch, part shade |
| Orange pustules under leaf, yellow spots above | Rust | Remove leaves, copper fungicide |
| Sudden curl, water-soaked patches, after cold night | Cold damage | Fleece protection, wait for new growth |
Frequently asked questions
Why are my anemone leaves curling?
Anemone leaves most often curl because of powdery mildew infection in warm, dry conditions with restricted airflow, or aphid colonies feeding on tender new growth. For Japanese anemone, vine weevil damage is also a frequent cause of wilting and leaf curl in late summer. Inspect leaf surfaces for white powder and stems for insects to narrow down the cause.
Does Japanese anemone get powdery mildew?
Yes. Japanese anemone (Anemone x hybrida and related species) is susceptible to powdery mildew, particularly in sheltered positions with poor airflow and during warm, dry summers. The mildew causes a white dusty coating on leaf surfaces and mild upward curling. Removing affected leaves and improving air circulation are the most effective first steps.
Can anemone leaves curl from drought?
Yes. Anemone prefers consistently moist soil and suffers in prolonged dry conditions. The leaves roll inward to reduce water loss during drought. Apply organic mulch to conserve moisture and water deeply at the base of the plant during dry spells. Japanese anemone in full sun is especially prone to drought stress.
What causes anemone leaves to curl and wilt in late summer?
Late-summer wilting and leaf curl on Japanese anemone is often caused by vine weevil larvae eating the roots underground. Check by lifting a struggling plant to look for white C-shaped grubs. Drought stress and powdery mildew can cause similar symptoms but the soil moisture level and presence of insects in the soil distinguish them.
Why do my spring anemone leaves curl?
Spring anemones (Anemone blanda, A. coronaria) often show leaf curl from aphids colonizing new growth, or from late frosts damaging tender emerging leaves. Check for insects on stems and buds. Cold-damaged leaves typically have water-soaked or translucent patches that turn brown as temperatures warm.