How to Get Rid of Katydids: Effective Removal Methods

Most katydids are harmless leaf-eaters that rarely cause enough damage to justify an all-out pest-control effort. When they do become a problem, particularly for fruit growers dealing with scarred citrus, the most effective strategy combines nighttime hand-picking, habitat modification, and targeted low-toxicity sprays. Reaching for broad-spectrum chemical pesticides is almost never warranted and carries risks that go well beyond your garden.

Do Katydids Actually Need Removing?

Before you declare war, it helps to know what you’re dealing with. Katydids are large, leaf-shaped insects closely related to crickets and grasshoppers. Most of the roughly 250 species found in North America feed on leaves, flowers, and the occasional smaller insect. In a typical backyard garden, a few katydids nibbling on foliage rarely produce visible harm. They chew a leaf here and there, but healthy plants outgrow the damage without any intervention.

The situation changes when katydids target fruit. Fork-tailed bush katydids, for instance, are a recognized pest in California citrus. Research on clementine mandarins documented a wide range of damage from these insects, from shallow surface cuts covering a small fraction of the fruit to deep holes that consumed the entire fruitlet down to the base. Surviving fruit developed substantial scarring at harvest, with large, deep, scabby marks that made the fruit unmarketable.¹ If you’re seeing that kind of cosmetic or structural damage on fruit, you have a reason to act. If a handful of katydids are chirping from your shrubs at night and you mainly find a few chewed leaves, the honest answer is that you probably don’t need to do anything.

Identifying When Katydids Are the Culprit

Katydids are nocturnal feeders. You’ll hear them before you see them: they produce the loud, rhythmic calls that fill summer nights in much of North America. If you suspect katydid damage but aren’t sure, go out after dark with a flashlight. Their large size (typically 4 to 6 centimeters for common garden species) and bright green coloring make them easy to spot on leaves and fruit once you know to look at night.

The damage they leave behind is distinctive too. On fruit, katydid feeding produces irregular, jagged scars and deep gouges that differ from the clean holes left by caterpillars or the stippled surface damage from thrips. On leaves, they chew from the edges inward, leaving ragged margins rather than the windowpane-like holes that beetles tend to create. If you’re finding damage but never seeing the insect during the day, nighttime is the key. Katydids spend daylight hours motionless and camouflaged, blending in with foliage so well that they are effectively invisible.

Hand-Picking and Physical Barriers

For home gardens, the simplest and most effective approach is physical removal. Katydids are big, slow, and not aggressive toward people. They don’t bite in any meaningful way. Go out after dark, pluck them off your plants, and drop them in a bucket of soapy water. This sounds tedious, but katydid populations in residential yards are usually low enough that a few nights of hand-picking makes a noticeable dent.

If the problem is concentrated on fruit trees or a vegetable patch, lightweight fabric netting works well as a barrier. Fine mesh draped over a small tree or staked over a garden row prevents katydids from reaching the fruit while still allowing light and water through. For individual fruit clusters on larger trees, organza bags or mesh sleeves tied around the developing fruit serve the same purpose. These physical methods have zero ecological downside and are often more effective than sprays, since a determined katydid can simply return after a spray has dried.

Reducing What Draws Them In

Katydids are strongly attracted to artificial light at night. If your porch lights, landscape lighting, or security floodlights are on all evening, you’re essentially running a katydid beacon. Switching outdoor lights to yellow or amber “bug bulbs” reduces their attractiveness to night-flying insects, including katydids. Motion-activated lights that stay off most of the time are another good option. Simply turning off unnecessary outdoor lighting after dusk can make a surprising difference over a few weeks.

Dense vegetation and ground cover near your garden also create favorable katydid habitat. Tall grasses, weedy borders, and thick shrub plantings provide the sheltered, leafy environment katydids prefer for daytime hiding. You don’t need to clear-cut your landscaping, but keeping vegetation trimmed back in the immediate vicinity of vulnerable plants reduces the number of katydids that set up residence nearby. Removing leaf litter and debris around the base of fruit trees eliminates egg-laying sites, since many katydid species deposit eggs in soil or among fallen plant material.

Neem Oil, Insecticidal Soap, and Other Low-Toxicity Options

When physical removal and habitat changes aren’t enough, several low-toxicity sprays can help without the ecological baggage of synthetic pesticides.

• Neem oil: Derived from the neem tree, this botanical pesticide disrupts insect feeding and development. It works best as a deterrent rather than a quick kill. Spraying neem oil on foliage and developing fruit makes them less palatable, discouraging katydids from settling in. Reapply after rain or heavy watering, as neem washes off.
• Insecticidal soap: Contact sprays made from potassium salts of fatty acids kill soft-bodied insects on contact by disrupting their cell membranes. Katydids are tougher than aphids, so insecticidal soap is less reliably lethal on large adults, but it works better on nymphs (the juvenile stage) and functions as a feeding deterrent on treated surfaces.
• Spinosad: A naturally derived insecticide produced by soil bacteria, spinosad is effective against a range of chewing insects. It has low toxicity to mammals and breaks down quickly in sunlight. Apply it in the evening to minimize exposure to pollinators, which are less active after dark.
• Kaolin clay: Sold as a fine white powder that gets mixed with water and sprayed onto plants, kaolin clay creates a gritty physical barrier that irritates and deters feeding insects. It’s widely used in organic fruit production. The white film washes off harvested fruit easily, though it does make your trees look like they’ve been dusted with chalk.

All of these options require direct contact or repeated application to be effective. None of them will wipe out a katydid population in a single spray. Their advantage is that they degrade quickly and pose minimal risk to beneficial insects, birds, and pets when used as directed.

Why Broad-Spectrum Chemical Pesticides Are a Last Resort

It can be tempting to spray a synthetic pyrethroid or a systemic insecticide and be done with it, but the downsides are real. A case study from California illustrates the risks well: in 2005, investigators documented an incident where cyfluthrin, a pyrethroid pesticide being applied to an orange field specifically to control katydids, drifted into an adjacent vineyard and made 27 workers sick. The investigation prompted a search for safer alternatives to broad-spectrum pesticides for katydid control.² That’s an agricultural-scale incident, but the principle applies to residential use as well. Pyrethroids don’t distinguish between the katydid you want gone and the ladybugs, lacewings, and parasitic wasps that are keeping your other pest populations in check.

Neonicotinoid insecticides, another common systemic option available to home gardeners, pose particular risks to bees and other pollinators. Research has established that neonicotinoids are highly toxic to bees, persistent in the environment, and broadly harmful to both managed honeybee colonies and wild bee populations.³ Systemic neonicotinoids applied to flowering plants or nearby soil can end up in pollen and nectar, poisoning pollinators that have nothing to do with your katydid problem. For a pest that is, in most residential contexts, a minor cosmetic nuisance at worst, the tradeoff simply isn’t worth it.

If you’re a commercial grower dealing with significant crop losses, the calculus is different, and professional pest management advice tailored to your specific situation and local regulations makes sense. For home gardeners, exhaust the lower-impact options first.

Protecting Citrus Trees

Citrus growers have the most reason to worry about katydids. The fork-tailed bush katydid is the primary culprit in California citrus, and the damage it inflicts varies substantially depending on which type of citrus you’re growing. Research comparing citrus species found that fruit damage at harvest was consistently lower in mandarin varieties than in sweet oranges, even after accounting for differences in tree age, grove size, and location.⁴ Scarring on mandarins and clementines was much lower than expected given the number of katydids present on those trees, suggesting that the fruit itself resists damage rather than simply being avoided.

A closer look at mandarin varieties confirmed this pattern. When fork-tailed bush katydids fed on a mandarin cultivar in controlled tests, they only scratched the surface of the fruit rather than chewing the deep holes commonly seen on sweet oranges. The superficial cuts that did occur were barely distinguishable from background weathering by harvest time.⁵ In contrast, clementines sustained a wider range of damage, including deep holes and irregular scabby scars, though still less than sweet oranges typically experience.¹

For backyard citrus growers, the practical takeaway is straightforward: if you’re planting new citrus trees and katydids are a known issue in your area, mandarin varieties will give you fewer problems than sweet oranges or grapefruits. For existing sweet orange trees, focus protective measures like netting and neem oil sprays during the period when fruit is small and developing, as that’s when katydid feeding causes the worst scarring. Mature, thick-skinned fruit is less vulnerable.

Encouraging Natural Predators

Katydids have plenty of natural enemies. Birds, bats, spiders, lizards, and parasitic wasps and flies all prey on katydids at various life stages. Creating habitat for these predators is one of the most sustainable long-term strategies for keeping katydid populations low. Birdhouses, bat boxes, and brush piles all encourage predator diversity in your yard. Avoiding broad-spectrum pesticide use is just as important here: you can’t invite predators in and poison them at the same time.

Parasitic tachinid flies and certain wasp species lay their eggs on or in katydids, and the developing larvae eventually kill the host. You can’t buy these parasitoids at the garden center the way you can ladybugs, but they’re naturally present in most areas and will find katydid populations on their own if you aren’t spraying them out of existence. Native flowering plants, especially those in the carrot and daisy families, provide nectar and pollen for adult parasitoid wasps and help sustain their populations between katydid outbreaks.

Timing Your Efforts to the Katydid Life Cycle

Most common North American katydid species have a single generation per year. Adults appear in mid to late summer, mate, lay eggs in soil or on plant stems in autumn, and then die with the first hard frosts. Eggs overwinter and hatch the following spring, producing small nymphs that go through several molts before reaching adulthood.

This life cycle creates a natural calendar for control efforts. Early summer, when nymphs are small and soft-bodied, is the most effective time for sprays like insecticidal soap or spinosad. Young nymphs are more vulnerable to contact insecticides than armored adults, and treating early prevents them from reaching the reproductive stage. By the time you hear adult katydids calling in August, you’re dealing with fully grown, tough insects that are harder to kill with low-toxicity products. Hand-picking adults is still effective, but you’ve missed the window for easy spray control.

In the fall, you can reduce next year’s population by disturbing potential egg-laying sites. Lightly tilling the top layer of soil around previously infested plants exposes overwintering eggs to cold, desiccation, and predators. Removing dead plant stems and leaf litter where eggs may have been deposited also helps. These steps won’t eliminate every egg, but they chip away at the population before the next generation hatches.

When a Katydid Gets Inside Your House

A single katydid that has wandered indoors through an open window or door is not an infestation. It got lost following a light source. The simplest solution is to turn off indoor lights near the katydid, open a door or window to the outside, and turn on an exterior light. The insect will fly toward the outdoor light on its own within a few minutes. If you’d rather not wait, gently scoop it into a cup with a piece of paper over the top and release it outside. Katydids don’t breed indoors, don’t eat household materials, and don’t establish colonies in buildings. If you’re finding multiple katydids indoors, the issue is gaps around windows, doors, or vents that need sealing, not an indoor pest population.

Keeping window screens in good repair and sealing cracks around door frames addresses the entry problem at its source. As with outdoor populations, reducing exterior lighting near windows and doors cuts down on the number of katydids bumping against your house in the first place.

Katydids in the Vegetable Garden

While most of the formal research on katydid crop damage focuses on citrus, home vegetable gardeners sometimes notice katydid feeding on leafy greens, beans, squash, and herbs. The damage is usually cosmetic and limited. A single katydid might chew irregular holes in a few leaves of basil or kale overnight, but it’s rare for the feeding to significantly reduce yield. If you’re growing vegetables for market and appearances matter, floating row covers are the most reliable defense. For personal use, the occasional chewed leaf is an acceptable trade-off for a garden that supports a healthy insect ecosystem.

One exception to the “mostly harmless” rule is young seedlings. A katydid that finds its way into a tray of newly transplanted seedlings can mow down small plants quickly, since there’s so little foliage to spare. Protecting seedlings with lightweight row cover or individual plant cloches during their first few weeks outdoors eliminates the risk without any spraying.