Slug Eggs in Soil: How to Identify & What to Do With Them

Gardeners know that there are many pests that can be a red flag to even the most green-thumbed enthusiast or expert, and slugs are often top of the list when it comes to causing gardening havoc. They’ll eat leaves and seedlings, while reachable fruit isn’t out of the question either.

To avoid slugs becoming a nuisance in your green space, in this article, I’ll be sharing how to identify slug eggs and prevent them from becoming a problem.

What Do Slug Eggs in Soil Look Like?

The first step to solving your slug egg problem is learning how to identify them. Slug eggs usually come in clusters – there’s never a single egg, and there can be more than 80 eggs in a single cluster!

Depending on the exact species and age of the eggs, they can be white, yellow, brown, or even transparent. Eggs will become darker as they mature and get close to hatching.

They’re also slimy since slugs release slime whenever they move to lubricate their movement.

Both snails and slugs lay their eggs on the surface or in a hole in the soil. After laying the eggs, they’ll cover them with some organic material to protect them.

what do slug eggs look like

Eggs or Soil Beads?

A common oversight that can easily be made by even the most experienced gardener is mistaking soil beads for slug eggs. It just so happens that these two, completely unrelated things, are similar in shape and color.

Soil beads are fertilizers that you’ll often find in potting soil. To put it simply – they’re great for soil and you don’t want to pick them out.

You can tell the difference between snail eggs and soil beads by size and grouping. Soil beads are usually smaller and they’re more similar to insect eggs in size. They’re also not tightly grouped nor covered in slime.

So, if you find a lot of beads sprinkled in your soil, they’re most likely soil beads, not snail eggs.

What’s Different About Snail Eggs?

The most obvious difference between slugs and snails is the slugs’ lack of a shell. When it comes to their eggs, though, the difference is almost imperceptible.

The only way to tell a snail egg from a slug egg is by closely examining the eggs. Snails are born with their shell (even though it’s transparent and mushy before calcification), and you might be able to see the shell in the egg.

However, it’s important to point out that both snails and slugs are a danger to your garden, and the methods of getting rid of them are the same. Therefore, the slug egg-snail egg difference isn’t really important.

Is Slug Larvae a Problem?

Slug eggs in soil are most definitely a problem! A single slug can’t cause too much damage, but slugs usually come in great numbers. 

They usually lay eggs several times a year (no more than 6 times), and it can take anything from two weeks to a month for them to hatch (depending on species and environment).

This means that they reproduce incredibly fast, and you can quickly have an entire colony of slugs and snails wreaking havoc in your garden in less than a growing season.

What Damage Do Slugs Do to Plants?

Slugs will eat more-or-less any plant you put in front of them. Although they prefer decaying plant material and fungi, they’ll also eat carrots, lettuce, cabbage, tomatoes, and basically any other vegetable out there.

Low-hanging fruit or fruit that has fallen on the ground isn’t safe either, as they’re famous for loving strawberries and apples.

Lastly, they’ll eat flowers and herbs too, so your flower garden is just as unsafe as your vegetable garden.

Slugs prefer leaves and soft fruits and vegetables as it’s easier to eat. They have raspy tongues and microscopic teeth, so they can’t bite with the same force other animals can.

You’ll recognize the work of a slug by the mucous trail that they leave behind. Slugs need to lubricate the bottom of their body to move, and the trail can stay behind for hours, if not days.

slug damage to plants

Laying Eggs & Hatching

If you’re sure you have a slug problem, the only way to get rid of them is to eradicate their eggs and prevent the slug population from expanding. To do this, you’ll have to find the egg clusters and remove them.

Where Do Slugs Lay Their Eggs?

Slugs will lay their eggs in a hole in the ground (the hole usually isn’t big) and cover it with organic material for protection. If possible, they’ll lay the eggs under a large log or a similar object that can cover the eggs and protect them from the elements.

Slugs and snails prefer moist soil to dry soil – something to keep in mind when you’re looking for eggs.

How Long Before Eggs Hatch?

If it’s not cold, you probably have a few weeks before your garden is overflowing with slugs. Most slug eggs hatch in less than a month.

However, eggs laid in late winter can take up to 5 months to hatch. The eggs can’t hatch during the winter because it’s too cold, and they need heat to develop.

How Quickly Do They Breed?

Slugs breed incredibly quickly – a single slug will lay over 500 eggs during its lifetime. The fact that they’re hermaphroditic definitely helps, as they can mate with literally any other slug they find.

A slug can lay eggs six times a year, and it takes no more than six months for a newborn slug to reach maturity and breed. Given that they lay anything from 3 to 80 slug eggs in the soil during a single mating period, you could potentially have thousands of slugs in your garden within a year.

However, this is the worst-case scenario. Slugs are near the bottom of the food chain and they’re easily picked out by hundreds of species feeding on them.

How to Remove Slug Eggs

The only way to end the infestation is by removing and destroying slug eggs. To remove them, you’ll have to pick them up with a trowel or gloves – they’re bound together by slime, so the egg clusters can easily fall apart.

If you just pick them up with your hand they’ll easily slip out. After picking them all up, put them in a bucket.

What to Do with Slug Eggs?

There are two options – you can throw them away, preferably far away from your home (or anyone else’s, for that matter). This way, they won’t hatch near your garden and cause any trouble.

Your other option is to destroy the eggs by pouring saltwater into the bucket. Saltwater (and salt in general) is a general killer for slugs.

You might be wondering why not just pour salt water into the soil? You could, but salt is unhealthy for soil and it’s smarter to pour it into the bucket and dispose of it somewhere other than your garden.

How to Prevent a Slug Infestation

Aside from destroying the eggs, it is a good idea to control the number of slugs in your garden. If there are no slugs, there are no slug eggs!

A solution containing microscopic nematodes is a quick and easy way to eradicate slugs from your garden and it has a high success rate. 

It works by infecting slugs with bacteria that kill them. You can buy nematode solutions in most garden centers and applying them to soil is a very effective slug-control method.

Slug pellets are another effective pesticide. However, they can be dangerous for your pets, so it’s only safe to use them if you can guarantee that your pets won’t get to them. Pellets are usually spread around plants and slugs die after eating them.

When using a pesticide, make sure you’re well-informed about all the dangers and always use it according to the instructions on the label.

You can also find slugs, pick them by hand and throw them away. This method isn’t that effective, though, as other slugs will find their way to your garden. You would need to go on a slug hunt every other evening to keep your garden safe, and this is time costly.

A great way to remove slugs is to allow predators into your garden – birds and hedgehogs, for example, eat slugs. However, some of these predators could be omnivorous which means they might end up eating both slugs and produce from your garden.

Contrary to popular opinion, barriers such as bark mulch and eggshells are not as successful as once thought in reducing slug numbers. Even if they were, you would have to set up a barrier around every single plant in your garden, and those barriers would have to be renewed every now and then.

Therefore, chemical solutions are by far the best way to keep slugs away from your garden.

To Sum Up Slug Eggs in Soil

Slugs love soft fruits and vegetables, as well as stems and leaves, which makes them a very real danger to any garden. They also breed crazy-fast, and it’s possible that several slug generations can develop in your garden within a single year.

However, slugs are easy to deter. Not only are they prey for many animals, but they can also easily be killed by pesticides, while slug eggs can be killed with saltwater.

Slug eggs look like clusters of tiny, slimy balls that can be white, yellow, brown, or transparent. After finding them, you can kill them with saltwater or throw them far away.

FAQ: Slug Eggs in Soil