Coral bells have been one of my go-to plants for adding color to shady spots, especially when I want something that looks good without much fuss. But a few summers ago, I noticed holes in the leaves and some plants looking downright ragged.
Turns out, even these tough little perennials have their weak spots. At first, I panicked and thought I’d have to spray something strong, but I didn’t want to mess with the bees and good bugs hanging around. So I started digging into gentler options—and thankfully, there are plenty that work just as well without throwing off the balance in the garden.
Now, I’ve got a few natural tricks up my sleeve for when pests show up. They keep my coral bells looking great and my conscience clear. Let me show you what actually works, so you can skip the stress and enjoy those vibrant leaves again.
1. Vine Weevils
Tiny notches along leaf edges are the first sign these sneaky beetles have moved in. Adult weevils feed at night, while their grubs attack the roots underground, potentially killing your entire plant if left unchecked.
Spread diatomaceous earth around plants as a natural barrier that damages the weevils’ exoskeletons. Beneficial nematodes make excellent biological controls when watered into soil during late spring or early fall when larvae are active.
Last summer, I discovered these pests after noticing several coral bells suddenly wilting despite adequate water. Checking the soil revealed the characteristic C-shaped grubs. Applying nematodes saved my remaining plants within weeks.
2. Aphids
Clusters of tiny green, black, or white insects gathering on new growth signal an aphid invasion. These sap-suckers distort leaves and stems while excreting sticky honeydew that attracts sooty mold, further stressing your coral bells.
A strong spray of water knocks aphids off plants, often solving minor infestations. For persistent problems, mix 1 tablespoon of dish soap with a quart of water and spray affected areas every few days until they’re gone.
Encouraging natural predators has worked wonders in my garden. Planting sweet alyssum nearby attracted hoverflies whose larvae devoured aphid colonies before they could establish on my prized ‘Palace Purple’ heucheras.
3. Slugs And Snails
Ragged holes in leaves and silvery slime trails across foliage reveal these nocturnal mollusks have been feasting. Young, tender coral bells are particularly vulnerable to severe damage, especially during wet periods when slugs and snails thrive.
Create barriers using copper tape around pots or beds, as the metal gives slugs a mild electric shock when touched. Alternatively, scatter crushed eggshells, diatomaceous earth, or coffee grounds around plants to create rough surfaces they avoid crossing.
My most effective solution has been evening patrols with a flashlight after rain. Handpicking these pests reduced their population dramatically in just two weeks, saving my newly planted ‘Caramel’ heuchera from becoming an expensive mollusk buffet.
4. Spider Mites
Mysterious stippling on leaves and fine webbing between stems signals these nearly microscopic arachnids at work. During hot, dry spells, spider mites multiply rapidly, sucking plant juices and causing foliage to appear dusty, yellow, and unhealthy.
Regular strong sprays of water disrupt their colonies and increase humidity, which these pests hate. For serious infestations, try neem oil spray weekly, being sure to coat leaf undersides where mites typically hide.
One summer during a drought, my ‘Obsidian’ coral bells developed a concerning speckled appearance. Increasing humidity by grouping plants together and misting regularly stopped the infestation before it could spread to neighboring perennials.
5. Cutworms
Finding your coral bells mysteriously cut off at soil level overnight points to these nocturnal caterpillars. Cutworms curl around stems before chewing through them, often destroying young plants completely within a single night’s feeding.
Protect stems with DIY collars made from cardboard toilet paper tubes or plastic cups with bottoms removed. Push these an inch into the soil around each plant, creating a barrier cutworms can’t navigate.
After losing several new transplants last spring, I began sprinkling used coffee grounds around vulnerable plants. The abrasive texture deters these soft-bodied pests, plus adds a nitrogen boost as the grounds break down – a double win for your garden.
6. Whiteflies
Clouds of tiny white insects that fly up when disturbed reveal a whitefly problem. Similar to aphids, these sap-suckers weaken plants and spread disease while leaving behind sticky honeydew that attracts black sooty mold.
Yellow sticky traps capture adults and help monitor populations. For natural control, spray plants with insecticidal soap or neem oil, focusing on leaf undersides where eggs and nymphs develop.
The first time I encountered whiteflies, I underestimated their persistence. Regular treatments every 5-7 days proved necessary to break their life cycle, as new adults continued emerging from eggs protected from previous sprays. Consistency was the key to finally eliminating them.
7. Japanese Beetles
Skeletonized leaves with only veins remaining indicate Japanese beetles have arrived. These metallic green and copper insects feed in groups, quickly turning beautiful coral bell foliage into lacy remnants during their summer feeding frenzy.
Hand-picking beetles in early morning when they’re sluggish provides immediate control. Drop them into soapy water to prevent escape. Avoid Japanese beetle traps, which can actually attract more beetles to your garden than they catch.
Neighbors often ask why I plant geraniums near valuable plants like coral bells. The secret? Japanese beetles become paralyzed after feeding on geraniums, making them easy to collect from beneath these companion plants each morning.
8. Root-Knot Nematodes
Mysteriously stunted growth and yellowing leaves despite good care might indicate these microscopic soil-dwelling worms. Infected roots develop characteristic swellings or knots that disrupt water and nutrient uptake, slowly weakening your coral bells.
Solarizing soil by covering moist ground with clear plastic during hot summer months can reduce populations. Adding organic matter regularly improves soil health and encourages beneficial microorganisms that help suppress these harmful nematodes.
After diagnosing this problem in my garden bed, I began annual applications of beneficial nematodes that prey on the harmful species. This biological approach gradually improved plant health without chemicals, though patience was necessary as recovery took almost a full growing season.
9. Thrips
Silvery stippling and streaking on leaves accompanied by tiny black specks (frass) reveal thrips feeding damage. These slender insects rasp plant surfaces to feed, causing distorted growth and spreading viruses that can permanently affect coral bells.
Introduce beneficial predators like minute pirate bugs and predatory mites that feed on thrips. Alternatively, spray plants with insecticidal soap or neem oil, making sure to thoroughly cover all surfaces including leaf undersides.
During a particularly bad infestation on my ‘Lime Rickey’ heuchera, I discovered that blue sticky traps work better than yellow for monitoring and catching adult thrips. This simple color change made a noticeable difference in controlling these difficult-to-see pests.
10. Leaf Miners
Winding, snake-like tunnels within leaves signal leaf miner larvae feeding between leaf surfaces. While primarily cosmetic, severe infestations can reduce photosynthesis and stress plants, especially during hot weather when coral bells are already challenged.
Remove and destroy affected leaves at the first sign of damage to prevent larvae from completing their life cycle. Covering plants with floating row covers during adult fly activity periods prevents egg-laying on vulnerable foliage.
Regular applications of neem oil have proven surprisingly effective in my garden beds. The oil doesn’t kill existing miners but disrupts their life cycle by preventing adults from laying viable eggs, gradually reducing populations over several weeks.
11. Scale Insects
Small, bumpy growths that don’t brush off easily from stems or leaf undersides indicate scale infestation. These immobile insects attach permanently to plants, sucking sap through protective waxy or armored coverings that shield them from many treatments.
For light infestations, dab individual scales with an alcohol-soaked cotton swab to dissolve their protective coating. Horticultural oils suffocate these pests and can be applied during dormant seasons for preventative control.
After struggling with recurring scale on several coral bells, I introduced lacewing larvae as biological control. These voracious predators seek out and consume scale insects, even getting under their protective coverings. Within weeks, the problem had noticeably diminished without any chemical intervention.
12. Mealybugs
Cotton-like white masses in leaf axils or along stems reveal mealybug colonies have established. These sap-feeding insects excrete honeydew that leads to sooty mold, while their feeding causes distorted growth and yellowing foliage on coral bells.
Isolate affected plants immediately to prevent spread. Dab visible bugs with alcohol-soaked cotton swabs for immediate control, then spray with insecticidal soap or neem oil solution to manage remaining populations.
The most surprising solution I’ve found came from my grandmother – a weekly spray of diluted milk (1 part milk to 9 parts water). The proteins in milk apparently break down the mealybugs’ waxy coating while also fighting the sooty mold that often accompanies infestations.
13. Earwigs
Ragged holes in leaves and flowers that appear overnight might be the work of earwigs. Despite their fearsome appearance, these nocturnal insects with pincer-like appendages are actually omnivores that sometimes help gardens by eating other pests like aphids.
Create simple traps using rolled newspaper or cardboard tubes placed near plants. Check and empty these hiding spots each morning. Alternatively, set out shallow dishes of vegetable oil with a drop of soy sauce as bait near affected plants.
When earwigs damaged my prize ‘Fire Alarm’ coral bells before a garden tour, I discovered they avoid crawling over diatomaceous earth. Creating a protective circle around special plants provided immediate protection without harming beneficial insects that fly rather than crawl to my plants.
14. Strawberry Root Weevils
Notched leaf edges similar to vine weevil damage, but typically more numerous and smaller, indicate strawberry root weevils. The larvae feed on roots while adults emerge at night to feed on foliage, gradually weakening coral bells from both directions.
Beneficial nematodes applied to soil provide excellent biological control of the larvae. For adults, create night traps by placing boards near plants – weevils hide underneath during daylight hours and can be collected and destroyed each morning.
Gardening near berry farms made this pest particularly troublesome in my landscape. Adding a thick layer of pine needle mulch created an uncomfortable surface for adult weevils to cross while simultaneously improving soil conditions for my acid-loving coral bells – a perfect dual-purpose solution.
15. Leafhoppers
Tiny wedge-shaped insects that jump or fly when disturbed indicate leafhoppers have found your coral bells. Their feeding causes stippled yellowing on leaves and can transmit plant diseases that cause further decline in plant health and appearance.
Reflective mulches like aluminum foil or silver plastic confuse these pests and reduce infestations. Insecticidal soaps provide contact control, but must hit the insects directly to be effective, so spray in early morning when they’re less active.
After battling recurring leafhopper problems, I began interplanting marigolds among my coral bells. The strong scent seems to repel these jumping pests, and I’ve noticed significantly less damage since adopting this companion planting strategy. As a bonus, the gold flowers complement the colorful heuchera foliage beautifully.