How do I stop slugs eating my plants?

Slugs are the most common cause of seedlings disappearing overnight. Control is about protecting the vulnerable plants during their vulnerable period rather than eliminating slugs, which is not achievable.

What you'll need

• Torch
• Barriers or collars (optional)
• Nematodes (optional)

Step by step

1. Go out at night with a torch and collect them.Unglamorous and the most effective single method by a clear margin. An hour after dark on a damp evening, particularly around vulnerable seedlings.
2. Protect the vulnerable plants specifically.Seedlings, hostas, lettuce, dahlias. Established plants tolerate slug damage; young plants do not survive it. Concentrate effort there.
3. Use physical barriers around individual plants.Cut-off plastic bottles as collars for seedlings work very well and cost nothing. They protect during the weeks that matter.
4. Use nematodes for a serious problem.A biological control watered onto moist warm soil. It works well against slugs but not snails, and timing and soil conditions matter.
5. Remove daytime hiding places near vulnerable plants.Long grass, upturned pots, planks, dense low foliage. Reducing shelter near the plants that matter reduces the population reaching them.
6. Water in the morning rather than the evening.Slugs move at night in damp conditions. A garden watered in the evening is considerably more attractive to them.
7. Encourage predators.Birds, frogs, hedgehogs, ground beetles. A pond and some undisturbed habitat does more over a season than most treatments.
8. Grow vulnerable plants on until they are large enough.Starting seedlings in pots and planting them out at a decent size avoids the most vulnerable period entirely.

Tips

• Beer traps work but they also kill beneficial ground beetles, which eat slug eggs. On balance they may not help.
• Copper tape, eggshells, coffee grounds and wool pellets are widely recommended and have limited measured effect. Barriers and hand collecting are what work.
• Some slug species eat mainly decaying matter rather than living plants. Not every slug in the garden is a problem.

Common mistakes

• Relying on folk remedies — Eggshells, coffee grounds and copper tape have little measured effect. Physical barriers and hand collecting are what actually protect plants.
• Planting out small seedlings unprotected — They disappear overnight. Growing them on in pots until they are larger avoids the most vulnerable period.
• Watering in the evening — Damp conditions at night are exactly when slugs are active. Morning watering makes the garden less attractive to them overnight.

Questions people ask