Epimedium, barrenwort or fairy wings, is one of the most valuable shade ground-cover perennials available. Its heart-shaped, often attractively marked leaves cover the ground densely, suppressing weeds and tolerating the dry, rooty conditions under trees that defeat most other ground covers. In spring it produces nodding, spidery flowers in yellow, white, pink, purple, or orange depending on the species, and many forms also develop attractive red, bronze, or copper tints on their new and older foliage. Epimedium is generally one of the most problem-free perennials in the garden, but it does have specific vulnerabilities, and leaf curl is the first sign that something is wrong. The causes are usually identifiable and fixable once you know what to look for.
1. Vine weevil
Vine weevil is the most serious pest of epimedium and the most common cause of leaf curl that does not respond to watering. The adult beetles feed on leaf margins at night, creating the characteristic scalloped notches around leaf edges. More damaging are the soil-dwelling larvae, which feed on the rhizomatous roots and rootstocks through late summer and autumn. Root damage causes the plant to wilt and the leaves to curl despite adequate soil moisture, since the damaged root system cannot take up water effectively. Severe larval infestations can kill entire sections of an established ground-cover mat. Container epimedium is particularly vulnerable because the larvae complete their development rapidly in the confined root ball.
What to look for
- Scalloped or notched leaf margins, particularly on older leaves
- Leaves curling and wilting despite moist soil
- Plant sections lifting easily from the soil when tugged
- Curved, white, C-shaped grubs with a brown head in the root zone when dug
- Adult beetles (grey-black, flightless, about 1 cm long) found under plant debris at night
How to fix it
Apply a nematode soil drench containing Steinernema kraussei in late summer or early autumn when soil temperatures are above 5 degrees Celsius. This is the most effective, reliable, and environmentally safe control method. For container epimedium, remove the plant, shake all compost from the roots, handpick visible grubs, and repot in fresh compost before applying nematodes. Check for adults by torchlight on the plant after dark in late spring and early summer and handpick them. Adults cannot fly, so physical barriers (copper tape, grit mulch) around containers deter females from reaching the compost to lay eggs.
2. Drought stress
While mature, well-established epimedium is justly famed for its drought tolerance, newly planted specimens need consistent moisture throughout their first season while the rhizomatous root system spreads and establishes. In dry spells in the first year, the leaves curl at the margins and develop a slightly dull, grey-green appearance. This is particularly common in summer plantings or in gardens with very free-draining, sandy soils. Once the plant is established (typically by year two or three), it becomes genuinely tough and self-sufficient in all but the most extreme droughts.
What to look for
- Leaf margins curling inward, particularly on newly planted specimens
- Slightly dull or grey-green colour on affected leaves
- Soil dry when probed below the surface
- Symptoms concentrated in the first growing season after planting
- Recovery after deep watering
How to fix it
Water newly planted epimedium regularly throughout its first growing season, particularly in dry spells. Apply a generous mulch layer to retain moisture while the root system establishes. Once established, epimedium in a suitable shaded position very rarely needs supplemental irrigation. When planting in hot, dry conditions, water thoroughly before and immediately after planting and maintain irrigation for at least the first three months.
3. Leaf scorch and wind damage
Epimedium prefers shade or dappled light and suffers leaf scorch when positioned in too much direct sun or in exposed, windy positions. The attractive, often patterned leaves develop brown, crispy margins and tips that curl around the scorched edges. In very cold, exposed positions, winter wind scorch damages the semi-evergreen foliage, causing it to curl, bronze excessively, and develop dead patches before spring renewal. Some species and cultivars are more tender than others: the deciduous species generally cope better with exposure than the evergreen types.
What to look for
- Brown, crispy leaf margins and tips with curling around the damage
- Damage concentrated on the side of the planting exposed to prevailing wind or direct sun
- Winter browning and curling on semi-evergreen forms in cold, exposed gardens
- New spring growth emerging clean and healthy even when older leaves are scorched
- Symptoms without any sign of pest activity or soil dryness
How to fix it
Move epimedium to a more sheltered, shadier position if sun or wind scorch is a recurring problem. Cut back badly scorched semi-evergreen foliage in late winter before new growth emerges: this is good practice regardless, as it reveals the spring flowers and allows the new leaves to develop without competition from the old. In the short term, remove the worst-affected leaves to improve the plant's appearance while new growth replaces them.
4. Slugs and snails
Young epimedium foliage is targeted by slugs in spring, particularly as the new leaves unfurl and are at their softest. Mature epimedium leaves become leathery and considerably less palatable to slugs than other shade perennials, so established plants typically suffer much less slug damage than young ones. Slug feeding produces ragged holes and eaten edges that curl around the damage. In the first season, slug pressure can be severe enough to delay establishment significantly, so control is more important for young plants than for established ground-cover mats.
What to look for
- Irregular holes in young, unfurling leaves
- Leaf margins eaten and curling around damaged areas
- Slime trails on and around the plant
- Damage worst overnight and after rain on young spring growth
- Established plants showing only minor damage compared to new plantings
How to fix it
Apply iron phosphate slug pellets around newly planted epimedium in spring when the young leaves are unfurling. A nematode drench provides sustained control in the first season. As the plant matures and the leaves toughen, slug control becomes less important. Grit mulch around new plantings discourages slugs from crossing to the young foliage.
5. Virus
Virus infections can affect epimedium, causing irregular mosaic patterns of light and dark green alongside distortion and curl of the leaves. Epimedium mosaic virus and cucumber mosaic virus have both been recorded. Viral infection typically causes asymmetric, irregular distortion quite different from the uniform drought curl or the notched margins of vine weevil. Virus is transmitted by aphids and through vegetative propagation from infected stock. Infected plants should be removed to prevent spread.
What to look for
- Irregular mosaic or mottled pattern of light and dark green on leaves
- Leaves distorted or puckered in irregular, asymmetric patterns
- New growth emerging already distorted at the point of unfolding
- Symptoms appearing across multiple plants in a planting
- No response to watering, pest control, or fungicide treatment
How to fix it
Remove and destroy infected plants, including all rhizome material. Do not propagate from any plant showing mosaic or distortion symptoms. Control aphid populations on nearby plants to limit virus spread. Source replacement plants from reputable suppliers using certified virus-free stock. Disinfect tools used on infected plants before using them elsewhere.
6. Root rot
Epimedium tolerates dry conditions but not waterlogged ones. In poorly drained positions, particularly heavy clay soils with poor drainage, the shallow rhizomatous root system can develop rot. Affected areas of the ground-cover mat brown, wilt, and die out in patches, with the leaves in affected sections curling and yellowing despite wet soil. Root rot on epimedium is much less common than vine weevil damage but more likely in gardens with heavy clay or compacted soil.
What to look for
- Patches of the ground-cover mat dying out with wilted, curling leaves
- Soil in affected areas consistently wet or waterlogged
- Brown, soft rhizomes in the affected patches when dug
- Healthy growth on nearby higher or better-drained ground
- Problem after prolonged wet winter or in low-lying areas
How to fix it
Remove and discard all affected material. Improve drainage in the affected area by incorporating grit into the soil. Epimedium in reliably moist but freely drained soil does not develop root rot; it is specifically stagnant waterlogging that is damaging. Where drainage cannot be improved, raised beds or mounded planting on a slight slope move the root zone above the waterlogged zone.
Quick diagnosis checklist
| Symptoms | Most likely cause | First action |
|---|---|---|
| Notched leaf margins, wilt in moist soil, grubs at roots | Vine weevil | Nematode drench in late summer |
| Margin curl, dull colour, dry soil, first season plant | Drought stress | Deep water + mulch, irrigate reliably in year one |
| Brown crispy margins, exposed or sunny position | Leaf scorch / wind damage | Relocate to sheltered shade, cut back scorched foliage |
| Holes in young spring leaves, slime trails | Slugs | Iron phosphate pellets + nematode drench on new plants |
| Mosaic pattern, asymmetric distortion, no pest found | Virus | Remove and destroy infected plants |
| Patches dying in wet soil, brown soft rhizomes | Root rot | Improve drainage, remove and discard affected material |
Frequently asked questions
Why are my epimedium leaves curling?
Epimedium leaves most often curl because of vine weevil larval damage to the roots (which causes the characteristic drought-like wilt and curl even in moist soil) or drought stress during the establishment period in young plants. Check for vine weevil by examining the root zone: curved white grubs with a brown head confirm the diagnosis. Established epimedium is quite drought tolerant, so drought curl is most common in plants in their first season.
How do I treat vine weevil on epimedium?
Apply a nematode soil drench containing Steinernema kraussei in late summer or early autumn when soil is above 5 degrees Celsius. This is the most effective and environmentally friendly treatment. For container epimedium, remove the plant from its pot, shake off all compost, pick out any grubs by hand, and repot in fresh compost before treating with nematodes. Adults are nocturnal and can be found by torchlight on the plant in late spring and early summer.
Should I cut epimedium back?
Many epimedium species are semi-evergreen or evergreen and can be cut back in late winter or early spring before new growth emerges. Cutting back the old foliage allows the attractive spring flowers to be seen clearly without the previous year's leaves competing, and stimulates fresh growth. Deciduous epimedium can be cut back to ground level in autumn. Avoid cutting back more than once a year.
Can epimedium grow in dry shade?
Yes, mature established epimedium is one of the most reliable plants for dry shade, a notoriously difficult combination that defeats most ground covers. However, it needs consistent moisture in its first growing season while establishing. Once the rhizomatous root system is well developed, typically by year two or three, epimedium tolerates remarkably dry conditions under trees where competing roots remove most available moisture.
Why are epimedium leaf edges turning brown?
Brown leaf edges on epimedium most often indicate wind scorch in exposed positions, frost damage on semi-evergreen or tender varieties, or drought stress on newly planted specimens. Established epimedium in a sheltered shade position rarely shows significant brown edges except at the end of the season before the old leaves are replaced. If browning occurs on new spring growth, late frost or cold wind is the likely cause.