Ants in Lawns: Solutions That Work

Written by Daniel Woodley. Reviewed by Hannah Miller. Published to Lawn Care on 14th November 2021. Updated: 24th February 2023.

Our editors publish helpful guides and insights learnt from years of experience and recent research. They also test, review and suggest plants and products. If you buy something via links, we may earn a commission, but we have a strict editorial process.

Lawn ants can undoubtedly be a nuisance, and while they rarely kill grass, the mounds that form above their nests are unattractive, and your lawnmower blades are likely to scalp the raised grass, possibly even damaging the roots too.

The good news is you don’t need a bucket of nasty chemicals, you can leave the boiling water safely in the kettle, and you don’t need to wait forever for my preferred method to work either.

My name is Daniel, and I’m the co-owner here at DIY Gardening; let me help you solve your lawn ant problem.

My Recommend Lawn Ant Product (It’s Organic Too!)

I’ve used several products to get rid of ants and other pests in the lawn and my number one organic choice is nematodes.

There are plenty of reasons why you should choose an organic ant treatment product:

  • Safe for wildlife and pets.
  • Safe for children.
  • Better for the environment.
  • Bee and pollinator friendly.

Never heard of nematodes?

They are tiny microscopic worms that you add to a watering can; once applied to the lawn, they attack the ants, which will relocate to a safer area.

Nematodes occur naturally in the environment, but you can buy them in a packet and apply them from April to October, provided the ground isn’t frozen.

Step by Step Instructions to Get Rid of Ants in Lawns

Nematodes are live worms, albeit tiny – over 16 million of them per packet! 

As they are alive, I’ve found that you should only order them when you are ready to use them or store them in a fridge as per the manufacturer’s guidelines.

Here are the step-by-step instructions, based on my experience:

  • Choose a wet or moist day; avoid dry weather conditions if possible.
  • Create a stock solution of water and nematodes in a bucket as per the guidelines on the packet.
  • Dilute the stock with water into watering cans and apply with a coarse rose.
  • Apply evenly to the entire lawn.
  • Keep the lawn moist for two weeks after application; otherwise, the nematodes will die.

What Happens Next

The nematodes irritate the ants who see them as a threat, the ants then migrate to a new area to get away from them.

The ants sense the nematodes and see them as parasitic predators, so they usually migrate far away, but it’s best to treat the entire lawn, so they don’t set up a home within your grounds again.

I’ve used nematodes before and also worked with gardeners who have used them and I’ve seen it take up to two weeks before the ants moved on.

Issues and Problem Solving

I’ve worked with gardeners who have had issues with this method and this is usually due to the nematodes dying before they’re had the chance to force the ants to relocate.

If the soil is allowed to dry out, the nematodes will die as they thrive in moist ground conditions.

If this happens to you, you’ll probably need to apply a second dose, which is a pain as nematodes are alive and can only be stored in a fridge for a short time.

Also, don’t forget that you shouldn’t put weed killers, moss products and fertilisers on the lawn for at least 6 weeks as they will kill the nematodes.

Ant hill in a l;awn

Typical ant hill in a lawn

Organic Suggestion #2

An alternative to nematodes is Diatomaceous Earth which is the crushed remains of fossilised diatoms.

This is widely used as an insecticide, and the product is 100% natural, safe for pets and children, and suitable for organic gardening.

I’ve used Diatomaceous Earth on carpets, hard surfaces and on my lawn and it does work, although I found on the lawn it took a few applications to get the job done.

I’ve seen people use this on crawling insects such as ants, silverfish, fleas etc. and it can also be used as a physical barrier to stop them from entering your home.

Diatomaceous Earth has many uses, including as a stabiliser for dynamite and as a filtration aid.

I suggest buying food-grade DE, which isn’t expensive.

Chemical Alternatives to Get Rid of Ants in Lawns

I prefer using organic products in my garden whenever possible as they’re better for the environment, pets and children, and to be honest, they do work very well.

I’ve used natural predators such as nematodes before to get rid of pests without using nasty chemicals.

That said, there are occasions when I reach for the chemicals, although it’s usually after trying safer options first.

I’ve tested various products and I’ve discovered the best chemical to get rid of ants in lawns is Permethrin in powder/dust form.

Just apply this powder on a dry day and keep pets and children away.

After a few days, the powder can be swept into the lawn, but I usually wait until the anthill has been vacated or the ants in the lawn are dead.

Strong Lawn Ant Killer Powder

This is the best nuclear option, and I’ve used this product before, and it certainly does the job.

Use indoors or outdoors on any surface where ants can be found.

Nippon ant killer contains permethrin at 0.488% in powder form, which is ejected from the bottle by squeezing it.

When I tested it, I applied it liberally to the ant nest and trod it down to disturb the ants.

I’ve also applied it to crevices, runs and entrances near the property that the ants used and it worked very well at stopping them.

Permethrin will kill any crawling insect and some flying, such as wasps, butterflies and bees, so I suggest only using it when there’s no other choice.

Do Ants Kill Lawn Grass?

Ants rarely cause direct damage to lawns, and although a large ant nest can destroy the roots, I feel this is the exception rather than the rule.

The main issue I have encountered is the mounds of earth that push up the grass, which I then damage by mowing.

On the other hand, ants help aerate the soil and are generally beneficial to the gardener, so I feel they should only be treated when necessary.

Salt, Vinegar and Boiling Water – Myths Debunked

Salt is toxic to the soil, so it shouldn’t be used on lawns at all, and it’s questionable as to whether it will get rid of ants in lawns anyway.

Vinegar doesn’t kill ants but disrupts their ability to track pheromones, thus confusing them. I’ve tried it as a repellent with mixed results, but I’m confident it won’t destroy a lawn ant nest.

Boiling water will kill the grass, so it shouldn’t be used on lawns.

Meet The Author: Daniel Woodley

Daniel has over 18 years of experience in the construction, home improvement, and landscape garden industries.

He previously worked as a project manager and has experience in managing teams of tradespeople and landscape gardeners on both small and medium sized projects.

Daniel is also a keen gardener and enjoys growing unusual plants and tending to his lawn.

More About Daniel Woodley.

Daniel Woodley

Our Experience of Getting Rid of Lawn Ants

Here at DIY Gardening, we follow a detailed, rigorous process to create content that is helpful, factually correct and meets the highest standard of integrity.

Our 5-step process is:

1) We select a topic that we feel will help our readers.

2) The author creates the content based on their knowledge and experience of the subject.

3) We ask an expert with qualifications or experience in the relevant area to fact-check and review the content, which we update accordingly, if applicable.

4) The content is then checked by the site owners and published.

5) We review the content yearly to ensure it’s still correct and relevant.

Daniel Woodley created this guide. He has experience in dealing with lawn pests, including chafer grubs and ant hills, the latter of which caused his lawnmower blades to wreck the grass.

Daniel has successfully treated ant infestations by using nematodes, he chose this method as he has a dog and didn’t want to put nasty chemicals onto the lawn.

This guide was reviewed and fact-checked for accuracy by Hannah Miller.

Explore: Hannah’s profile and qualifications.

Explore More of our Lawn Guides Below:

All LAWN GUIDES

Our lawn guide articles are very popular and have helped thousands of gardeners in the UK. Learn how to grow grass in shade, deal with pet urine, wear and tear, weeds and moss control. Start Here

Best Moss Killer For Lawns

We’ve tested and reviewed the best lawn moss killers you can buy in the UK. Let us help you get rid of moss and let your lawn grass thrive and grow with our expert help and guidance. Start Here

Over 40 Lawncare FAQS

We asked the experts and they answered our questions in detail. Discover over 40 answers to common lawn care questions here at DIY Gardening. We think this is a great resource! Start Here

This guide to getting rid of ants in lawns was created by Daniel here at DIY Gardening

About Us