How to Identify Caterpillar Damage on Your Plants

Identify Caterpillar Damage

CAUTION: Caterpillars can do GREAT damage to your plants. Be vigilant! The good news? Caterpillar damage is fairly easy to identify on your plants. Look for gaping holes, missing edges to your leaves, or heck, entire leaves missing from your plant! It happens. It’s not fun, but it is reality. Identifying damage early is crucial, which is why I suggest visiting your garden every day.

You don’t have to weed, or plant, or do any chore while you’re there. Simply stroll through your beds and admire the work of Mother Nature. Remember, plants grow all by themselves in nature without your help–you’re just an assistant here. (Lucky you!)

As you’re strolling through your garden, look at your leaves. If you see holes or damage, stop, and inspect your plants more closely. This is when you’ll spot the little beasts responsible. And once you identify the damage, you’ll want to act quickly.

Signs You Have Caterpillars

So when you’re inspecting your plants and looking for caterpillars, be aware that they are sometimes VERY hard to spot. Take the tomato hornworm pictured below. When small, I often miss these worms because they blend extremely well with the leaves and stems. They also tend to hide under leaves, which means you must inspect closely. Another sign to watch for is caterpillar frass, otherwise known as poop.

If you see these deposits on your plants, do not give up until you locate the “creator” of said poop. He’s there. Somewhere. Unless of course a bird snatched him. Our winged friends enjoy feasting on worms, so by all means, welcome them to the garden. Hornworm frass is much larger, shown center of the image, and a sign your worms are larger, too. Yikes!

Remove Caterpillars

The easiest and quickest way to remove caterpillars is to pluck them off your plant and relocate the critters elsewhere. Where? That’s up to you. Just get them off your plant, before they kill it. One of the best prevention methods is Bt (Bacillus Thuringiensis Kurstaki), a biological insecticide control for Tomato Hornworm, Looper, Webworm, Armyworm, Cutworm, Leaf Roller, and other caterpillars on vegetables, fruits, ornamentals, flowers, and lawns. It comes in dust form (Dipel Dust) or liquid form. Both work, though I prefer the dusting powder. Dipel dust works as a stomach poison and must be ingested to be effective. Works best on smaller caterpillars.