The short version
Slugs do most of their damage at night and in damp weather, on young seedlings, and they can clear a row in one night. Every barrier method works partially. Going out with a torch works completely, and takes ten minutes.
What you need
A torch
Genuinely the most effective tool there is.
A bucket
For collecting. Deal with them however you prefer.
Rough mulch, if you want a barrier
Grit, wool pellets or bark. Partial help, not a solution.
How to do it
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Go out an hour after dark
Especially after rain. That is when they feed, and when you can find them.
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Check the underside of leaves and pot rims
They shelter where it is damp and dark by day.
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Protect seedlings specifically
Young plants are the vulnerable stage. Established plants shrug off a lot of nibbling.
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Clear the daytime hiding places
Boards, dense weeds and pot saucers are where they wait out the day.
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Water in the morning, not the evening
A damp bed at dusk is an invitation.
When it goes wrong
Seedlings gone overnight
- Slugs
Silvery trails confirm it. Nothing else removes a whole seedling that cleanly.
Ragged holes in leaves
- Slugs
- Snails
Irregular holes with smooth edges, worst after rain.
Damage with no trails
- Caterpillars
- Birds
Look again by day. Slug damage almost always leaves a trail somewhere near it.
Frequently asked questions
Do beer traps work?
They catch slugs, including ones that would have walked past. Useful, but not a substitute for looking.
Are slug pellets safe?
Ferric phosphate pellets are approved for garden use and are less risky to wildlife than the older metaldehyde ones, which are banned in many places. Follow the label.
