There are many ways you can keep your slug population under control without resorting to toxic slug pellets:
- Encourage beneficial wildlife in your garden – from insects right through to frogs and hedgehogs. Make sure that you have a range of habitats available. Wild patches, log piles and damp shady places around the garden will ensure a wide range of wildlife is at home in your garden and keep pest populations under control.
- If you keep chickens or ducks then they will also help keep slugs at bay if you let them patrol regularly (although they may also help themselves to some of your plants!).
- Barriers can be used to keep slugs and snails away from prized plants. Slugs won’t cross copper, and so you can use copper pipe to edge a raised bed, or copper rings around individual plants. You can buy sticky copper tape and copper-infused mats that are useful for protecting containers. Cloches made out of plastic bottles will protect seedlings from bad weather as well as predators.
- Other barriers worth trying are soot, sand, crushed eggshells, coffee grounds or grit. Barriers tend to be made of gritty substances which irritate slugs, or ones that absorb moisture and make it hard for slugs to slime their way across.
- Slug ‘pubs’ are popular traps, usually a small pot buried in the soil and filled with beer. Trials suggest the slugs aren’t fussy which sort of beer is used, and will also fall for milk or bran. Slug traps should have a lip above the soil surface – slugs will be able to climb in, but other insects on the surface (including beneficial ground beetles) will be less likely to fall in and drown.
- If you’re in the midst of an infestation, you may want to go out at dusk or dawn and collect slugs by hand. They collect under stones and in damp nooks and crannies to hide out the sun. Try ringing your vegetable patch with a ‘trap crop’, sacrificial plants that slugs love (try lettuce) and which they will eat in preference to other plants. You will then know exactly where to find them every evening and they will probably leave your other vegetables alone.
- During spring and fall, the main egg-laying season, you can apply a biological control. Biological controls are microscopic predators, specifically designed to deal with one sort of pest. The biological control for slugs is a nematode worm, watered onto the soil, that kills off young slugs. This will prevent a population boom, but the adult slugs have to be dealt with using another method.
- As a final resort, it is now possible to buy environmentally-friendly slug pellets that are based on an iron compound. These pellets kill slugs without the potential damage to wildlife, pets and children of the usual pesticide slug pellets.
Slugs are a big problem in gardens where a moist, mild climate allows them to thrive. Each slug can eat twice its own body weight per day, and lays up to 300 eggs in spring and fall. It pays to have your slug control strategy in place early!
How do you deal with these pesky pests?
Check out my Gardening basics section for more sage advice and how to guides. Other articles you may find useful include coping with two-legged rats, how to repel pests with plants and how to deal with garden pests in an environmentally-friendly way.