How to Handle Slugs, Wireworms, and Beetles

Slugs, wireworms, and beetles are some of the most frustrating pests for potato growers, often hiding unseen until harvest. Early action and the right methods can keep your tubers healthy and hole-free.

Slugs

• Damage:
  Chew holes in tubers, especially in wet summers or heavy soils. May also eat leaves and stems.
• Prevention:
  • Earth up potatoes well so tubers grow deeper out of reach.
  • Use dry mulch (straw or leaf mold) and avoid overwatering.
• Control:
  • Hand-pick slugs at dusk, especially after rain.
  • Place beer traps (half-buried cups with beer) near beds to lure slugs away.
  • Scatter crushed eggshells, sand, or organic slug pellets (iron phosphate type) around plants.
  • Encourage hedgehogs, frogs, and ground beetles—nature’s slug patrol.

Wireworms

• Damage:
  Thin, orange-brown larvae of click beetles tunnel into tubers, leaving them riddled with holes.
• Prevention:
  • Avoid planting potatoes in newly converted grassland—wait a year or more if possible.
  • Chop up raw potato pieces, bury them 5cm (2in) deep as “traps”; check every few days and remove wireworms.
  • Practice crop rotation and avoid continuous potato cropping.

Potato Beetles (Colorado Potato Beetle)

• Damage:
  Adults and striped, orange larvae skeletonize leaves. Rare in some regions but a serious pest.
• Prevention & Control:
  • Inspect leaves regularly and squash any beetles or bright yellow eggs under leaves.
  • Use row covers to block adults if beetles are present in your area.
  • Remove weeds in the nightshade family (help reduce beetle habitat).
  • Beneficial insects like ladybugs and predatory stink bugs help control larvae.

Extra Tips

• Keep potato beds well weeded and clear of plant debris—many pests like to hide here.
• Rotate beds yearly to break pest life cycles.
• Encourage birds and wildlife that patrol your garden for insects and slugs.