Slugs are the torment of many gardeners; these small, stealthy gastropods crawl at night, eating the leaves and fruits of many plants. Before they take over and invade your beloved garden, you must take action to eliminate them and prevent them from ruining all your crops. Using different techniques, including baits and traps, and inserting natural predators that catch slugs for you, in no time you will be able to have the garden completely free. Keep in mind that all of these methods are equally effective for snails as well.
Steps
Method 1 of 4: Set Up Traps and Catch Slugs
Step 1. Set up beer or milk traps for important plants
Slugs are able to notice traps when they are about one meter away, so this method is more suitable for relatively small gardens or for the most important areas of the vegetable garden. Set the trap as follows:
- Bury a deep, steep-sided cup in the ground. Let the edge protrude 1.5 cm above ground level to prevent the trap from killing slug-catching beetles.
- Fill half the cup with beer or milk.
- Replace the contents every 2-3 days. If the slugs manage to climb to get out, replace the solution with a mix of honey, yeast, and some water, to boil until the mixture becomes sticky.
Step 2. Kill the slugs with a cornmeal trap
This is a cheaper remedy, but it cannot attract as many of these mollusks as possible. Put a tablespoon or two of corn flour in a jar and place the latter on its side. Make sure the cornmeal stays dry and you will see that it will kill the slugs by expanding in their abdomen.
Step 3. Lure slugs with non-cruel traps
Slugs are typically found most often in damp, dark areas, such as under wooden planks, flower pots, or in cardboard boxes. Set up similar environments and check them every day to collect live slugs and throw them away from your property. If you want to get the best results, get some of the following foods that slugs are fond of:
- Cabbage leaves.
- Citrus peels moistened with water.
- Dry food for animals.
Step 4. Protect the traps from rain and pets
The water would ruin the cornmeal and liquid traps, so install a cover so that the rain can't hit them. If you have pets that might eat the bait, put a sturdy cover like an upside-down flowerpot with a small slug entrance.
Step 5. Look for slugs at night
While not one of the funniest jobs, it may be necessary to catch slugs individually if you have a severe infestation problem. Grab a flashlight and put on disposable gloves, skewer the slugs with a stick, or drop them into a bucket full of soapy water. If you have one, use a headlamp that allows you to have both hands free, making work easier.
- Check the underside of the leaves.
- Follow the traces of drool you notice on the ground.
Method 2 of 4: Discourage the Slugs
Step 1. Keep your garden dry
You won't see results immediately, but keeping the grass dry is the best way to manage slugs in the long run. Here are some strategies to make your garden less attractive to moisture-loving pests:
- Water the plants during the first half of the morning, so that the soil dries out before night.
- Install a drip irrigation system to minimize water use.
- Keep the garden free of debris or debris and mow the grass regularly.
- Avoid putting mulch such as straw or cut grass.
- Plant the plants well spaced to allow for good air circulation.
Step 2. Make mulch or tea with some plants
Preparing the litter according to the following methods is very effective in somehow discouraging slugs; check if you can get the material from a nursery or garden center in your area:
- Mulch of oak leaves or tobacco stem meal, to be distributed all around the plants as a barrier.
- Wormwood tea obtained by macerating mugwort cuttings in hot water for 24 hours. Filter it, mix it with soap and water and spray it on the ground or directly on the slugs.
Step 3. Install a barrier with a copper strip
Purchase thin strips of copper that are wider than the body of the slugs and use them to form a barricade around any plants or flowerbeds targeted by the mollusks.
Be careful because small children can cut themselves with these strips
Step 4. Sprinkle salt on non-earthy surfaces
Pour salt on all surfaces where you see slugs crawling to kill them by dehydrating them. However, be aware that salt can easily kill plants and ruin the soil. Apply this method only around the base of the plants you keep in pots on a porch, on concrete bases, or place a barrier on the ground before spreading the salt, in order to protect the integrity of the soil.
Avoid using it in situations where there is the possibility of it coming into contact with water (when it is likely to rain or if a sprinkler is running). In fact, the water dissolves the salt and washes the "safe" surfaces by letting the salt enter the soil and thus ruining its quality
Step 5. Build traditional barriers
Frustrated gardeners have attempted to remove the slugs from their garden with every possible substance. The best home solutions are listed below, but it's not 100% sure you'll be able to completely discourage pests:
- Coffee grounds can have minor effects on the well-being of your garden.
- Coarse, sharp sand can scratch slugs, but does not completely drive them away.
- Algae are not as effective as salt, but they are perhaps a little safer for the soil. Calcified seaweed meal is definitely better if you can find it.
Step 6. Grow plants that discourage slugs
Some plants keep slugs away thanks to their flavor, texture, or toxins they contain. You can consider planting these strains to create a barrier all around your garden, or place one near each plant you want to protect. This is not a 100% effective method, but it undoubtedly discourages many slugs, without the need for special effort, other than to bury the plants. Try the following species:
- Herbs: ginger, garlic, chives, mint and chicory.
- Vegetables: Bitter ones usually attract slugs less than sweet ones. Try planting kale, cabbage, or Brussels sprouts.
- The blue-leaved Hosta genus is more hardy.
- Flowers that stand in full shade: Astilbe, Dicentra, Digitalis (digitalis), Lobelia, Viola (some pansies and violet). Also try Ranunculus (buttercup) and Vinca, although these spread quickly.
- Flowers that are in partial shade: Phlox, Campanula, Hemerocallis, as well as Mentha, although this spreads rapidly.
Step 7. Consider the idea of using more aggressive (but more dangerous) barriers
There are several materials that can kill slugs on simple contact. These can be used to create effective barriers to prevent slugs from moving, but great caution is needed and they are substances that must remain dry. If you use them improperly, you can cause damage to the garden (as well as to the people or animals that enjoy the outdoor space). Be sure to apply these substances only on constructed surfaces and not on soil, except where specifically noted:
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Safety warnings:
do not inhale any of these substances and do not handle them with bare hands. They may be unsuitable products in gardens where children or pets play.
- Diatomaceous earth: can harm beneficial insects.
- Wood ash: increases the pH of the soil, which can affect plants.
- Hydrated lime: significantly raises the pH of the soil and makes it uninhabitable for many plants.
- 1% caffeine in spray format: apply it directly on the plants you want to protect; kills slugs when they feed on them. It can negatively affect many plants in unpredictable ways.
Method 3 of 4: Using Natural Predators
Step 1. Introduce the carabidae
These are natural predators of snails. You can purchase the larvae at garden stores and distribute them throughout the garden in the spring. The larvae feed, enter the pupal stage, and are reborn as adult beetles in the summer.
Alternatively, you can encourage wild beetles to stay close to plants by providing them with a dry refuge under stones, grass, or straw. This way you make your garden a "cozy home" for these insects that can hide from predators. Fortunately, carabidae can live almost anywhere where slugs also live
Step 2. Use the birds to your advantage
The largest natural predators of snails are birds; ducks, chickens, robins, jays and other common species all eat snails. If you are not too picky, you can catch snails and throw them to wild birds in the morning; over time you will see that they will get into the habit of coming to look for slugs in your garden and at that point it will no longer be necessary to "feed" them for a long time. You can also let the chickens or ducks roam freely; if you have tamed some of them, they will eat garden snails every day.
- Keep an eye on your chickens, as they could also eat plants.
- Encourage birds to nest in your garden by leaving thick hedges or shrubs, bird feeders and even a drinking fountain.
Step 3. Place some toads on your property
These amphibians love snails and will eat them along with other plant pests if you provide them with a refuge in your garden. If you want to attract wild toads, turn a vase or other container upside down against a rock to create a dark hiding place. Alternatively, you can consider buying some and keeping them in the garden so that they regularly eat the slugs and get rid of these mollusks. You can also decide to install a small decorative pond for amphibians to entice them to settle in your garden.
Do not keep fish in the pond, as they may eat the tadpoles
Step 4. Insert nematodes into the soil if necessary
Nematodes are microscopic parasitic worms that live in the soil. You can purchase the species specifically suited for killing slugs at garden stores. This can be an extremely effective remedy, even if it is a double-edged sword. Once you have managed to kill all the slugs, their predators (and nematodes) leave the area or die. If you don't reapply nematodes on a regular basis every few weeks, a massive wave of snails could return to invade the garden and cause a serious infestation thanks to the lack of threats.
When purchasing nematodes, make sure that the instructions for use are also indicated. They generally need to be spread over the ground when it has been watered
Method 4 of 4: Using Chemicals
Step 1. Spray the slugs with ammonia
You can get a spray product to kill slugs by making a solution of water and ammonia. Mix 1 part household ammonia with 6 parts water. Pour the solution into a spray bottle and spray it on the snails whenever you see them. The important thing is that you do not use it directly on plants, because over time it could burn the leaves.
Step 2. Use ferric phosphate pellets
You can find this product in all garden centers and spread it around the garden. Slugs are attracted to it but, once ingested, they die within a week. This treatment is safe for most pets and edible plants, but it is recommended to use it as little as possible.
The most popular trade names are Ferramol, Sluxx and Derrex
Step 3. Test the metaldehyde
This is a common anti-slug treatment, but it has its limitations. Particularly, metaldehyde is very toxic to pets (especially dogs). It is essential to handle and place this bait correctly, to avoid creating dangerous situations for pets.
- Avoid "pellet" shaped metaldehyde, as it can be mistaken for treats by dogs. Instead, use the "granule" form.
- Keep it somewhere safe where dogs cannot access.
- Do not apply it near edible plants.
- Spread it in thin layers, never in piles, as pets may mistake it for food.
- Metaldehyde is most effective on mild dry days, but cannot be applied in sunlight. Spread it under the leaves the night before if you anticipate it will be a hot day.
- Look for products with a low dose of metaldehyde on the market, to have the lowest possible environmental impact.
Advice
If you catch slugs manually, look for them early in the evening, preferably when the weather is wetter, or early in the morning
Warnings
- There is some controversy over whether ferric phosphate pellets actually contain an ingredient that makes the solution toxic when applied. It is thought that it may contain EDTA (ethylenediaminetetraacetic acid) and that it is indicated as an inert ingredient.
- Slugs are shellfish, not insects, so common insecticides are not effective.
- Many snail baits that are advertised as safe actually contain toxins that can harm or kill a variety of invertebrates, including earthworms.
