Pest identification
What's eating my bean?
Mexican bean beetle (Epilachna varivestis)
Signs: Skeletonized leaves with a lacy appearance from adult and larval feeding on undersides
Control: Hand-pick adults, larvae, and yellow egg masses; apply neem oil; introduce parasitic wasp Pediobius foveolatus where available
Aphids (black bean aphid, Aphis fabae)
Signs: Dense black colonies on shoot tips; stunted and distorted growth; sticky honeydew; ants attending colonies
Control: Pinch out infested growing tips; blast with water; apply insecticidal soap; encourage ladybirds and hoverflies
Japanese beetle (Popillia japonica)
Signs: Leaves skeletonized, leaving only the veins; adults feed in clusters on upper surfaces of foliage
Control: Hand-pick into soapy water early morning; apply kaolin clay as a deterrent; pyrethrin spray as a last resort
Slugs
Signs: Seedlings severed at soil level or cotyledons stripped; slime trails present
Control: Iron phosphate pellets around seedlings; grit or bark mulch as a physical barrier; hand-pick at night
Keep bean pest-free
Healthy plants resist pests best. Get the basics right:
Bean pests — FAQ
What is eating my bean?
Beans are commonly attacked by Mexican bean beetles and aphids, which can devastate a crop quickly. Slugs target seedlings at germination. Japanese beetles skeletonize leaves in the US. Rabbits and deer browse bean rows readily in rural and suburban gardens. Spider mites can be severe in drought conditions.
How do I get rid of mexican bean beetle (epilachna varivestis) on bean?
Skeletonized leaves with a lacy appearance from adult and larval feeding on undersides Hand-pick adults, larvae, and yellow egg masses; apply neem oil; introduce parasitic wasp Pediobius foveolatus where available
How do I get rid of aphids (black bean aphid, aphis fabae) on bean?
Dense black colonies on shoot tips; stunted and distorted growth; sticky honeydew; ants attending colonies Pinch out infested growing tips; blast with water; apply insecticidal soap; encourage ladybirds and hoverflies
How do I get rid of japanese beetle (popillia japonica) on bean?
Leaves skeletonized, leaving only the veins; adults feed in clusters on upper surfaces of foliage Hand-pick into soapy water early morning; apply kaolin clay as a deterrent; pyrethrin spray as a last resort
How do I get rid of slugs on bean?
Seedlings severed at soil level or cotyledons stripped; slime trails present Iron phosphate pellets around seedlings; grit or bark mulch as a physical barrier; hand-pick at night