One of the most commonly found pests, slugs in garden and allotment areas can do significant amounts of damage in a surprisingly short amount of time. Capable of wiping out a collection of young flowers or vegetables in a night, they are often described as the gardener’s worst nightmare.
Keeping slugs in garden and allotment areas at bay, or even completely slug free, is, for many green fingered growers, the ultimate dream. But is this possible without resorting to chemical controls? Happily, the answer is yes. This article will take you through everything you need to know to deal with slugs in garden environments.
If allowed to, the slug can become an incredibly destructive pest.
What is a Slug?
Before we discuss how to safely and efficiently deal with slugs in garden and allotment areas we will first take some time to explore exactly what a slug is. This greater understanding of the little pests will help us as we attempt to combat their presence in the garden.
The slug is not actually an insect, unlike many other backyard irritants. In fact the slug is a land dwelling mollusk, more closely related to clams than caterpillars.
Unlike the snail, the slug doesn’t have a shell. Instead, on its back, is a small saddle-like plate known as the mantle. Due to their lack of protective shell the slug tends to avoid bright, sunny days. Preferring instead to emerge in rainy weather or at night, when they are protected from the sun. When the sun is out they can be found hiding under rocks and logs or in other dark, damp locations.
Unlike the snail, the slug doesn’t have a protective shell.
Slugs in garden or allotment situations can cause serious problems. Working out how to get rid of slugs in garden environments without resorting to chemical controls can seem impossible. But there are a lot of affordable and easy to use solutions.
Why are Slugs in Garden Environments so Problematic?
Not all slug species found in yards and allotments eat plants. A number of them are classed as decomposers. This means that they feed on decaying plant or animal waste. Decomposers are relatively harmless when it comes to protecting your precious plants. Some slug species, however, prefer to feed on living plant material. These are the problematic pests that gardeners dislike. If allowed to, they can cause significant damage.
It can be difficult to diagnose the presence of slugs in garden or allotment environments because they hide during large parts of the day. This makes finding the pests a tricky task.
Tender young leaves, such as lettuce leaves, are a popular target for the slug.
Gardeners noticing leaf damage that are unaware of the presence of a slug population in their flower or vegetable beds may spray affected plants with a general insecticide. These are designed to kill bugs and insects meaning that they are completely ineffective when it comes to stopping slug infestations.
What Does Slugs in Garden Damage Look Like?
Slugs in the garden like to target young seedlings and tender leaved plants. Older plants can be left with ragged holes in leaf edges and centers. They can also create perfectly round holes in soft fruits such as strawberries and tomatoes. Within a couple of hours the pests can completely destroy a crop of plants, leaving nothing but the leaf midribs.
In addition to damaging and deforming foliage the slug leaves another visible sign, revealing their presence in your yard. As they move around, the slug leaves a slime trail behind it. This can cover walls, plants, mulch and many other surfaces. It is the clearest indicator, apart from actually seeing them, that there are slugs in your garden.
A popular target, the holes in hosta leaves are a sure sign that a slug colony is present.
How to Deal with Slugs in Garden
There are a number of different ways to deal with slugs in garden or allotment environments. These range from basic solutions such as handpicking and disposing of the pests to organic traps and solutions. Here are some of the most effective.
Going out at night with a torch and a bucket of soapy water is a basic way to get rid of pests. Simply pick the pests from the foliage and drop them in the bucket. While this is a basic and effective solution, handling the slimy creatures can be difficult, not to mention unpleasant.
Similar to picking the pests, this is an easy way to trap a lot of creatures in one go. All you need to do is lay wooden 2×4 planks between your crop rows in late afternoon or as dusk falls. As night fades and the sun rises, slugs shelter beneath the planks to avoid the heat. The next afternoon simply flip over the planks to reveal the pests. Collect and dispose of them in a bucket of soapy water.
Instead of planks, you can use watermelon rinds to trap the pests.
Planting Sacrificial Crops
If you have the space, plant some excess crops or leave a pile of dried cat food or old lettuce leaves. The best place is a damp, shady corner. As the creatures start to congregate, scoop them up and dispose.
A popular way to deter slugs in garden and allotment environments is to lay beer traps. The pests are attracted to the yeast in the beer. After falling into the trap they drown. Simply empty the trap the next morning and refill.
A popular and easy to use solution, this is a great way to protect pots and planters. Just wrap the metal around the container. As the slug slithers over the band its slimy trail reacts with the copper to give the slug a mild electric shock. Copper Tape provides an easy way to protect planters and pots. However, this solution may not be ideal if you are trying to defend an entire backyard or allotment.
Create Slippery Barriers
Create slippery barriers by spraying WD-40 on the outside of pots or planters. This creates a slippery surface that pests find difficult to scale. When applying, make sure that you cover the entire surface.
Diatomaceous Earth and Mulches
Diatomaceous earth is a fine, sharp powder. If laid on the soil it can cut the skin of the slug as it crawls over the top of the surface, causing the pest to slowly bleed to death. While this can be an effective way to protect a small number of plants, diatomaceous earth is useless if it gets wet.
Other sharp edged items and mulches such as dried coffee grounds, ground up shells and crushed eggshells can also be used to deter these creatures.
Itchy and rough, the slug dislikes climbing over wool’s coarse texture. Organic pellets made from compressed natural wool and shaped into pellets can be spread around the base of vulnerable plants. Once watered the pellets expand, forming a thick mat of wool. This long lasting deterrent also deters weeds.
An old fashioned remedy to get rid of these pests is to sprinkle salt on them. If placed directly on the slug, salt can cause the pests to shrivel up and die. But this is not an effective solution. The slug may simply shed the affected layer and carry on destroying your plants. Additionally, excess salt can damage sensitive plants.
Use Organic Slug Bait
This is a reliable method to control slugs in garden and allotment environments. When sprinkled on the surface of the soil the bait stops a slug from feeding almost instantly. The creature dies a few days later. The safest baits can also be safely used in vegetable beds and around food crops.
When selecting your bait, be careful. Not all solutions are the same. Despite being considered organic, some can even be poisonous to pets and wildlife. Avoid baits that contain methiocarb or metaldehyde as an active ingredient. Both are dangerous. The latter is extremely toxic to mammals, a teaspoon is enough to kill a small dog.
Instead look for baits that have iron phosphate as an active ingredient. These tend to be safer. Some are even certified for use on organic farms. Products such as Sluggo contain iron phosphate making them not only safe to use around animals but also extremely effective.
Add Nematodes to Your Soil
Nematodes are soil dwelling microorganisms. They also live in the slug as a parasite. Adding them to the soil is an easy way to control slug populations. Simply mix with water and add to the soil. The soil temperature needs to be at least 41 ℉ for nematodes to be effective.
How to Prevent Slugs in Garden
Preventing the pests from becoming a problem is a lot easier than getting rid of slugs in garden and allotment environments. There are a number of simple steps you can take to deter the pests.
Firstly, avoid using loose mulches such as straw, wood or hay. Use a compost or leaf mold instead.
Avoid loose mulches such as straw, a slug can navigate these with ease.
Try to avoid watering plants later in the day. Slugs and their eggs thrive in wet conditions. Water early in the day so that the soil and plants are dry at night. Drip irrigation instead of overhead watering, so that the root zone is sufficiently watered and the foliage remains dry, also deters the pests.
Another way to deter the pests is to plant flowers and herbs that the pests dislike. They are particularly put off by herbs with fragrant foliage. They also dislike furry or fuzzy leafed plants. The colorful astrantia plant, a reliable herbaceous, emits a scent that repels slugs. Other plants that the slug dislikes include:
You can also keep slugs in garden numbers down by encouraging slug predators such as birds, lizards, toads, frogs and hedgehogs to the garden. Ground beetles also target the pests. Why not build a bug hotel to boost the number of natural predators and beneficial insects in your yard?
Another way to attract beneficial insects is to stop using chemical controls and pesticides. For example, firefly larvae predate newly hatched slugs. Lawn pesticides kill fireflies as well as other beneficial insects. Adopting organic lawn care methods helps to boost the number of fireflies and other useful insects in your backyard. This, in turn, helps to keep numbers down.
Our last suggestion for deterring slugs in garden or allotment environments is to have a tidy up. Removing potential slug shelters such as bricks, logs and even pieces of garden furniture helps to keep slug numbers down.
There are a number of safe and easy ways to control slugs in garden or allotment environments.
If left unchecked slugs in garden or allotment situations can cause enormous amounts of damage. However, as this guide shows, there are a number of easy, low maintenance solutions to keep your outdoor area slug free. Many of these are also safe to use around pets, children and edible plants.
Jen is a master gardener, interior designer and home improvement expert. She has completed many home improvement, decor and remodeling projects with her family over the past 10 years on their 4,500 sf Victorian house. She is also a passionate farmer who keeps goats, chickens, turkeys cows and pigs on her farm, and an instructor for her community’s Organic and Sustainable Farming project.