What Do Cutworms Look Like

If you’ve ever gone into your garden to find a young seedling completely severed at the base, you’ve likely met the cutworm. Knowing what do cutworms look like is the first step to stopping them. These sneaky pests are the culprits behind many a gardener’s frustration, and they can be tricky to spot because they do most of their work at night.

This guide will help you identify them, understand their lifecycle, and show you how to protect your plants with effective, garden-friendly methods.

Cutworms are not actually worms; they are the caterpillar larvae of several species of night-flying moths. They get their name from their habit of chewing through plant stems at ground level. Here’s how to recognize them.

Physical Appearance

Cutworm caterpillars are usually plump, soft-bodied, and can grow up to 2 inches long. They often curl into a tight ‘C’ shape when disturbed. Their color varies widely, which can make identification tricky.

Color: They can be gray, brown, black, tan, or even pinkish. Many have stripes or spots running the length of their bodies.
Skin: Their skin often appears greasy or smooth, not hairy like some other caterpillars.
Markings: Look for a series of dashes or dots along their sides or back.

Behavior & Damage Signs

You might not see the cutworm itself right away, but you’ll notice its handiwork. They feed primarily after dusk and hide in the soil or under debris during the day.

Cut Seedlings: The classic sign is young plants (tomatoes, peppers, cabbage, corn) cut cleanly at the stem near the soil.
Partially Eaten Leaves: On larger plants, they may climb and chew irregular holes in leaves.
Wilting Plants: Sometimes they damage the roots or girdle the stem without severing it, causing the plant to wilt and die.
Hiding Spots: Check just below the soil surface around a damaged plant; you may find the culprit curled up.

Cutworm vs. Grub: What’s the Difference?

It’s easy to confuse cutworms with white grubs, but they are different pests. Grubs are the larvae of beetles (like Japanese beetles) and have a distinct creamy white body with a brown head and six legs at the front. They are usually found in the soil feeding on roots, not cutting stems above ground.

The Adult Moth

The moths that become cutworms are generally dull-colored, brown or gray, and have a wingspan of about 1.5 inches. They are nocturnal and are often attracted to lights at night. Seeing these moths around can be a warning sign of a future infestation.

Common Types of Cutworms

Different species have slightly different habits, which can affect the damage you see.

Climbing Cutworms: These will scale plants to feed on buds, leaves, and fruits.
Army Cutworms: They sometimes move in large groups, like an army, across a garden.
Black Cutworms: A common species known for severe damage to a wide variety of crops.

Their Lifecycle in Your Garden

Understanding their lifecycle helps you time your defenses. Most cutworms have one or two generations per year.

Eggs: Adult moths lay tiny, round eggs on plant stems or in soil debris in late summer or fall.
Larvae: The eggs hatch into the destructive cutworm caterpillars. They feed and grow, causing the most damage in spring and early summer.
Pupae: After feeding, they burrow into the soil to pupate.
Adults: Moths emerge to start the cycle again. Some species overwinter as larvae or pupae in the soil.

How to Find Them in Your Garden

Since they hide during the day, you need to search strategically. Go out after dark with a flashlight and inspect the base of your plants. You can also gently dig in the top inch of soil around damaged seedlings. Another trick is to place a small board or piece of cardboard on the soil; cutworms will often congregate underneath it for shelter, allowing you to check in the morning.

How to Control Cutworms Naturally

Once you know what your dealing with, you can take action. A combination of prevention and direct control works best.

Prevention is Key

Stopping cutworms before they become a problem is the most effective strategy.

Till the Soil: Tilling in fall or early spring exposes pupae and larvae to birds and cold weather.
Clear Debris: Remove weeds, grass, and plant debris in the fall to eliminate egg-laying sites.
Delay Planting: If possible, plant seedlings a little later when they are sturdier and less vulnerable.
Use Collars: Create barriers around transplants. Push a collar made from cardboard, aluminum foil, or plastic cups (with the bottom cut out) 1-2 inches into the soil around each stem.

Direct Control Methods

If you find cutworms active in your garden, these methods can help.

Handpick at Night: With your flashlight, pick them off plants and drop them into soapy water. This is very effective for small gardens.
Encourage Predators: Birds, toads, ground beetles, and parasitic wasps are natural enemies. Provide bird baths and toad houses to invite them in.
Apply Beneficial Nematodes: These microscopic worms, watered into the soil, seek out and kill cutworm larvae. They are a safe biological control.
Diatomaceous Earth: Sprinkle a ring of food-grade diatomaceous earth around plants. Its sharp particles deter and dehydrate soft-bodied insects. Reapply after rain.
Create a Trap: Bury a small cup (like a yogurt container) level with the soil and fill it with a inch of beer or a molasses-water mixture. Cutworms will fall in and drown.

When to Consider Other Options

For severe, widespread infestations, you might consider an organic insecticide containing Bacillus thuringiensis (Bt), a naturally occurring bacteria that targets caterpillars. Always apply at dusk for maximum effect and follow the label instructions carefully. Chemical pesticides should be a last resort, as they harm beneficial insects too.

Checking for Success

After you implement control methods, monitor your garden closely. A reduction in new damage is your first sign of success. Continue to use collars on new transplants and maintain a tidy garden to prevent them from returning next season. Remember, a healthy garden ecosystem with lots of biodiversity is your best long-term defence.

FAQ: Common Cutworm Questions

What plants do cutworms attack?

They prefer young vegetable seedlings like tomatoes, peppers, cabbage, broccoli, corn, and lettuce. They also attack some flowers and lawn grasses.

Are cutworms active all year?

No, they are most active and damaging in the spring and early summer. The larvae feed and grow during this time before pupating in the soil.

Can a plant recover from cutworm damage?

If the stem is completely severed, the plant cannot recover. However, if the stem is only partially damaged or if the roots are intact, you can try to save it by burying the damaged stem section deeper in soil and keeping it well-watered.

How do I stop cutworms from climbing?

For climbing species, you can apply a sticky barrier, like Tanglefoot, around the stems of larger plants to prevent them from crawling up.

Do cutworms turn into butterflies?

No, they turn into moths. The adult moths are usually dull-colored and fly at night, often going unnoticed in the garden.

By learning what do cutworms look like and how they operate, you can take quick action to save your seedlings. With a watchful eye and these simple, natural strategies, you can protect your garden’s hard work and enjoy a healthy, productive season. The key is to be proactive and to check your plants regularly, especially during those vulnerable early weeks of growth.