Do cutworms only eat seedlings?

They prefer tender, young stems, but some species will feed on the roots or lower leaves of more established plants if food is scarce.

Why do I only see the damage in the morning?

Cutworms are nocturnal feeders, meaning they come out to eat at night and bury themselves in the soil to hide from the sun and predators during the day.

Cutworms

Symptoms by part

Stems

Young plants appear severed at the soil line, often leaving the top of the plant lying on the ground.

Roots

Some species feed underground, causing the plant to wilt, yellow, and eventually collapse as the root system is consumed.

Causes

High levels of organic matter or weeds in the garden bed that attract egg laying moths.
Cool, damp soil conditions during the early growing season.
Newly tilled soil that was previously covered in grass or weeds.

Could be confused with

Damping off · Damping off is a fungal disease that makes the stem look mushy or shriveled, whereas cutworm damage shows clean, jagged chewing marks.
Slugs · Slugs leave behind slimy trails and typically eat holes in leaves, while cutworms focus on cutting through the main stem.

Treatment

1. Search the soil surface around the base of damaged plants at night with a flashlight to hand pick and remove the larvae.
2. Dig gently into the soil within 2 inches of the stem base during the day to find and remove curled up larvae.
3. Apply Bacillus thuringiensis to the soil surface around the base of plants in the evening to target feeding larvae, follow the label.

Without chemicals

Place a cardboard collar or a bottomless plastic cup around the stem of each seedling, pushing it 1 to 2 inches into the soil to create a physical barrier.
Place a small stick or toothpick directly against the stem when planting to prevent the worm from wrapping its body around the plant.
Clear away weeds and debris from the garden bed at least 2 weeks before planting to remove hiding spots and food sources.

Chemical options

Bacillus thuringiensis, apply to the soil around the base of plants in the evening, follow the label.

Preventing it

Till the soil a few weeks before planting to expose larvae to birds and other predators.
Use physical barriers like collars on all new transplants.
Keep the area around your plants free of weeds and tall grass to discourage moths from laying eggs.

Season

The warm growing season, particularly during the spring when seedlings are most tender.

Spread risk

Low

Severity

High

When to act

Act as soon as you notice a plant toppled or wilting at the base. If the main stem is completely severed, the plant cannot be saved and should be removed.

Think it's Cutworms?

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Questions people ask

Do cutworms only eat seedlings?: They prefer tender, young stems, but some species will feed on the roots or lower leaves of more established plants if food is scarce.
Why do I only see the damage in the morning?: Cutworms are nocturnal feeders, meaning they come out to eat at night and bury themselves in the soil to hide from the sun and predators during the day.

Plants it affects

Creeping Buttonweed

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This guide was generated with AI and is general information, not horticultural advice. Read about how we build these guides.