← All pests
Corn Earworm

Corn Earworm

Helicoverpa zea

Insectalso: Tomato fruitworm

A single caterpillar that is the wormy tip of a sweet corn ear, the chewed hole in a tomato, and the borer in a bean pod, since it goes by corn earworm, tomato fruitworm, and other names for the same pest. On corn it feeds down from the silk into the ear tip.

🔎 How to spot it

The caterpillars grow up to about two inches and vary widely in color, from green to pink, brown, or nearly black, with pale and dark lengthwise stripes and a brown head. On corn, look for chewed, frass-packed silk and feeding in the top inches of the ear; on tomato, a watery, frass-filled cavity where the larva entered near the stem. The adult is a drab night-flying moth.

🥀 Damage it causes

On sweet corn the larvae feed on the silks and then down into the kernels at the ear tip, fouling it with excrement; on tomato and pepper they bore into the fruit, leaving a messy, rotting cavity; on beans they chew the pods. The first big generation finds the silking corn, and because the larva is sealed in the ear or fruit it is hard to reach once inside.

🛡️ Prevent it

On sweet corn, choose varieties with long, tight husks that wrap well past the ear tip, which slows the caterpillars. Plant early so ears silk before peak moth flights, and till under crop residue promptly after harvest to destroy the pupae in the soil. Scout silking corn and ripening tomatoes for eggs and young larvae.

🧯 If it is already here

A classic home trick on corn is to apply a few drops of vegetable or mineral oil (some gardeners add Bt or spinosad) to the silk just inside the tip a few days after silks appear, smothering larvae as they enter. On tomatoes and beans, Bt or spinosad works only if applied right after eggs hatch and before larvae bore in. Snip out the damaged ear tip at harvest and discard infested fruit.

💡 Good to know

Because one species wears so many names, the same caterpillar you find in the corn is the one boring your tomatoes, which is why managing it across the garden, and tilling under residue to kill the soil pupae, pays off. Once the larva is inside the ear or fruit, no spray reaches it, so timing on the silk and young fruit is everything.

🌱 Plants it attacks

103 plants in the library can be attacked by this pest

Adirondack Blue PotatoAdzuki BeanAji Amarillo Pepper🥔All Blue PotatoAmbrosia CornAmish Paste TomatoAnaheim PepperBanana PepperBeauregard Sweet Potato🍅Beefmaster TomatoBenarys Giant ZinniaBetter Boy Tomato🍅Big Beef TomatoBig Boy TomatoBlack BeanBlack Beauty EggplantBlack Cherry TomatoBlack Krim TomatoBlue Lake Green Bean🍅Box Car Willie TomatoBrandywine TomatoBroad Windsor Fava BeanBurgundy OkraCalifornia Giant ZinniaCannellini BeanCarolina GeraniumCarolina Reaper PepperCayenne PepperCelebrity TomatoCherokee Purple TomatoClemson Spineless OkraCranberry BeanCubanelle PepperEarly Girl TomatoEdamameFairy Tale EggplantFingerling PotatoFordhook 242 Lima BeanFresno PepperGerman Butterball Potato🍅German Queen TomatoGhost PepperGolden Bantam CornGreen Bell PepperGreen Zebra TomatoHabanero PepperHungarian Wax PepperIndigo Rose TomatoItalian EggplantJalapeño PepperJapanese EggplantJuliet Grape TomatoKellogg's Breakfast TomatoKennebec PotatoKentucky Wonder Pole BeanKidney Bean🍅La Roma IV TomatoLemon Boy TomatoMammoth SunflowerMaverick Geranium🍅Mortgage Lifter TomatoMr. Stripey TomatoMung BeanNavy BeanNorland PotatoOrange Bell PepperPadrón PepperPimento PepperPineapple TomatoPinto BeanPoblano PepperPopcornProCut Sunflower🌱Provider Bush BeanPurple Bell Pepper🥔Purple Majesty PotatoPurple TomatilloRed Bell PepperRed Noodle Yardlong BeanRed Pontiac PotatoRoma TomatoRomano Bean🍆Rosa Bianca EggplantRusset Potato🍅Rutgers TomatoSan Marzano TomatoScarlet Runner BeanScotch Bonnet PepperSerrano PepperShishito PepperSilver Queen Corn🍅Striped German Tomato🍅Sungold Cherry TomatoSweet 100 Cherry TomatoSweet Banana PepperThai Chili Pepper🍅Tiny Tim Cherry TomatoToma Verde TomatilloTorch Mexican SunflowerTrinidad Scorpion Pepper

For educational and informational purposes only. Pest control advice is general guidance drawn from university cooperative extension sources; always identify a pest positively and read and follow the label on any product before use, especially around food crops, children, and pets.