Different methods of getting rid of slugs and snails
Environmentally friendly methods
Deterrents
To reduce slugs and snails by environmental means try to deter them from the area. The following tips will help keep them out:-
Keep your garden tidy. By reducing available places for the
to shelter in weeds and rubbish. Avoid leaving pots, trays, plastic etc. around
the garden. This is especially important in cool damp parts of the garden.
Do not have hedges or grass borders next to susceptible plants.
Digging before winter frosts will help to reduce the numbers.
Digging in warm humid weather when slugs are active & near the surface
will expose eggs and adults to predators.
Where the problem is severe, digging can be followed by an evening stroll
to collect slugs that are active.
Bare soil & frequent hoeing / digging exposes eggs & adults to predators
& dehydration in dry weather. Eggs are laid shallow in the soil, about
30 / 200 together. They are white or transparent & 2 / 3 mm in diameter.
Big changes in soil temperature & humidity are fatal to the eggs. In drier
weather they are laid deeper in the soil or in cool dark places. Most eggs
are laid May & September - hatching in 1 to 3 weeks.
Finely worked soil eliminates ground cracks for hiding.
Drain wet or sour land.
Liming sour & acid soil significantly reduces the population of slugs
but overliming may encourage snails.
Improve soil structure with added well rotted compost, well worked in.
Try to grow plants that are more resistant to slugs or that slugs do not like.
Lift crops promptly, especially potatoes.
Carefully inspect newly bought in plants for signs of adults or for eggs.
Regularly inspect the underside of benches, pots, trays, water-hoses etc...Remove
any adults or eggs that are found.
Mow grass at dusk to kill slugs that are emerging for the night-time feed.
Environmentally friendly methods -
Collect them and place in a container with a lid (and holes) and move them to somewhere else.
Biological Control / Nematodes (Phasmarhabditis hermaphrodita) -
There is also
a biological control for slugs available commercially. They are especially
effective on the control of the smaller underground type slugs. These are
microscopic nematodes that kill slugs by laying their eggs in them. This involves
applying the microscopic Nematodes to the soil, either in liquid or powder
form. They do not harm any other insects and do not damage the soil.
They do have to be applied about every six weeks and usually have to be purchased
by mail order. The nematodes are less effective in ground that is well manured.
The other drawback is that they are expensive compared to other methods.
Encourage birds into your garden by providing a bird bath and suitable nesting places. Dense hedges usually encourage birds to nest in them. Thrushes in particular are very partial to snails. Rooks, jackdaws, jays, magpies, starlings, blackbirds, fieldfare, gulls, owls and robins all eat slugs and snails.
Hedgehogs are a natural predator of slugs and snails and can devour a great number every night. They can be attracted by providing winter shelter (piles of leaves etc.), and a little tinned cat or dog meat. Do not feed on bread and milk, as this is harmful to them.
Consider installing a pond to entice frogs or toads as they will help in keeping the population down. They will require a pond or water source with easy access; low dense plants or cover (logs, stones etc. ) to hide in during the day (they are mainly nocturnal). The larger the frog or toad, the bigger the slugs they will eat. Full size frogs and toads can eat snails as well although slugs form a very high proportion of their diet.
Do not kill beetles as the larvae of some ground beetles eat slugs. The adult beetles are energetic hunters of slugs. Unfortunately, they do not breed as fast as slugs & can't keep up with sudden slug increases. To encourage beetles, provide suitable Summer nesting sites such as piles of stones or logs etc. Many species are active for only a few weeks in Spring & Summer before entering a resting period before laying eggs in Autumn. They usually hunt under cover, under plants, debris, mulches, etc. Most species prefer moist shady conditions & feed mainly at night. A few are active in the day & prefer more open ground. Provide overwinter sites: under logs, tree bark, in the soil or in a patch of rough grass. Most tend to move to woodland or hedgerows in the Winter. In Spring & Summer, ground beetles eat many eggs & young slugs.
Common Shrews
They prefer cover, especially long rough grass, an undisturbed site for nest, especially a hole or burrow in the ground. Shrews diets consists of earthworms, beetles, spiders, woodlice & many slugs & snails. They remove the slime from slugs first. They hunt especially at dusk, night & dawn.
Slow Worms.
They require: an undisturbed spot, a compost heap is ideal. Vegetation, a sunny spot: woodland clearing, old ivy covered wall, hedge bank, railway embankment, corrugated iron sheet laid on the ground etc. They eat especially small white slugs, also other slugs & some snails. They are more effective after rain. They can live 30 years.
Centipedes
They require darkness, moisture, protection by plants, debris, stones, etc. They are completely carnivorous and eat insects, worms, slugs & snails.
Not the best of methods, but, if you have the way of accommodating them, ducks and geese will eat slugs. Poultry will also dig sufficiently to eliminate slug/snail eggs. (Beware! They also like plants)
Last updated
7 December, 2003
© copyright 1999, P. A. Owen