Organic Control of Night-Feeding Pests on Green Beans

Identifying the Stem-Cutting Culprit

Stems severed 2-3" above ground at night suggests:

• Cutworms: Caterpillars (noctuid moth larvae); curl around stems, chew through. Hide in soil by day.
• Voles/Mice: Gnaw stems; often leave distinct tooth marks. Your trapping success supports this.
• Flea beetles: Chew small holes in leaves—not stem cutting.

Organic Solutions

For Cutworms:

• Collars: Toilet paper rolls, yogurt cups (bottom removed), or aluminum foil pushed 1" into soil around each stem.
• Beneficial nematodes: Steinernema carpocapsae applied to moist soil at dusk.
• Diatomaceous earth: Ring around plants (reapply after rain).
• Bacillus thuringiensis (Bt): Spray on foliage evening; caterpillars ingest and die.

For Voles/Mice:

• Hardware cloth cylinders: ¼" mesh, 12" tall, buried 6", around each plant or bed perimeter.
• Capsaicin spray: Hot pepper wax or homemade (1 tbsp cayenne/quart water + soap) on stems—reapply frequently.
• Trapping: Continue snap traps in boxes (protect birds/pets) along runways.
• Habitat reduction: Remove mulch near stems; mow paths wide; eliminate brush piles.

Rotation Critical

10+ years same location = pest buildup. Rotate beans to new bed next year. Plant cover crop (rye, vetch) this fall to break cycles.