How can I control slugs without pellets?

Several methods work, and the effective approach is usually to combine two or three rather than relying on any one.

Nematodes are the most effective biological option. A microscopic parasite watered onto moist soil infects slugs underground and kills them within days. It works on soil-dwelling slugs rather than surface ones, is harmless to pets, wildlife and children, and typically lasts around six weeks per application. It is also the most expensive option and needs soil above roughly 5°C.

Encourage predators. Slugs are eaten by hedgehogs, frogs, toads, ground beetles, thrushes and slow-worms. A pond, a log pile, gaps under fences for hedgehogs, and avoiding pesticides that kill ground beetles will all reduce slug numbers over a season. This is slower than any direct method and more durable than all of them.

Physical barriers work with mixed results. Copper tape is widely sold; trial evidence for it is inconsistent. Sharp grit, wool pellets and crushed shells work better around individual vulnerable plants than as a garden-wide strategy.

Night patrols are unglamorous and genuinely effective. Slugs feed after dark and in wet weather; going out with a torch an hour after dusk removes large numbers quickly.

Beer traps catch slugs but also drown beetles that prey on them, so they can be counterproductive.

Timing and placement. Protect seedlings — which are what slugs destroy — and worry less about established plants. Water in the morning rather than the evening, so the surface is dry overnight.

If using pellets, ferric phosphate types are approved for organic growing; metaldehyde has been withdrawn in many countries over wildlife harm.