Living in the UK, slugs are a continual battle that I felt like I was always losing. That is until I discovered slug nematodes. These invisible little things have controlled my slug problem, and they are entirely natural to boot. So what are they, how do they work, and how do you apply them? Let’s find out.

What Are Slug Nematodes?
Nematodes are tiny, microscopic roundworms that live in our soil and water. There are huge numbers of different species of nematodes, but the ones we are interested in today are slug nematodes.
These are parasitic nematodes that prey on molluscs. They enter the slug and then release a bacteria that kills it. The nematodes then eat the slug and multiply.
They are perfectly natural and already present in your soil. By applying more of the nematodes, you are just increasing the numbers and, therefore, the number of slugs that they kill.
Benefits of Using Slug Nematodes
In this section, I will discuss the numerous benefits of utilising slug nematodes as a means of pest control in gardens and allotments.
Eco-Friendly Pest Control
One of the main reasons I recommend using nematodes for slug control is their eco-friendly nature. As microscopic worms present abundantly in the soil, nematodes provide a way to control slugs without causing harm to the environment.
Moreover, they’re approved for use in organic farming, given their natural occurrence and positive impact on maintaining a healthy ecosystem.
No Harm to Beneficial Species
When trying to control pests such as slugs and snails, one of my concerns is the potential harm to other beneficial organisms in the ecosystem. Thankfully, nematodes are highly specific in their target, ensuring that other species remain unharmed by their parasitic action.
This selectiveness allows for effective slug control without damaging other crucial species within the environment.
Reduced Chemical Usage
Using slug nematodes allows me to reduce the use of harmful chemical pesticides and garden organically. Chemicals may not only cause harm to non-target organisms but also contaminate soil and water, posing a risk to humans and the environment alike.
By choosing slug nematodes, I can effectively manage slug populations while keeping my surrounding ecosystem safe and healthy.
Before Applying
I like to apply nematodes twice a year, once in spring and then again in autumn. There are two main factors to bear in mind when applying nematodes. They don’t like cold weather and need it to be above 5 Celsius.
They also don’t like exposure to UV, so applying in the early morning or in the evening is recommended.
How To Apply Slug Nematodes

This is what you get inside the packet, it is a powdery substance that contains the nematodes and I would imagine some food to keep them alive.

You need to make a stock solution to begin with. You then dilute this solution later. How much water you need for your stock solution depends on the size of the pack you bought, but it does tell you on the back.

You then add all of the powder to your bucket of water and stir it in.

Then you take half a litre out of your stock and put it in a watering can. You then dilute this in your watering can with 5 litres of water.
You can then apply this to your garden soil. You need a course rose (big holes) on your watering can, or it can block.

You then repeat this process, adding 0.5 litres of the stock solution to your watering can, diluting it and then applying it to your soil. Keep going like that until you have used up all of your stock solution.
Where to buy slug nematodes
You can find them in some garden centres, but this is quite rare. That is simply because they are a short-lived product and don’t last on shelves, so many garden centres struggle to stock them.
I buy mine from Amazon. Once they are delivered, you need to use them as soon as possible, so don’t order too early in the spring when the soil is still too cold to apply them!
Control slugs NATURALLY by applying Nemaslug Slug Killer, which contains natural nematodes, that are effective at controlling slugs, but unlike chemical controls, are safe for children, pets, birds and wildlife.