How to kill ants nest in lawn - effective solutions that won't harm your grass

If an ants nest has found a home in your garden, here's how to get rid of it

Lawn bordered by flower beds and hedges leading to garden room
(Image credit: Future PLC/Carl Hodgson)

The pesky thing about ants is that they come in the thousands, so the last place we want them to nest is in our garden. Fortunately, you can learn how to kill ants nest in lawn and get back to enjoying your garden pest-free. 

Even if you know all the best lawn care tips and you take good care of your grass, an ant colony can still settle in your garden and build a nest. Anthills are a sure way to ruin the look of any garden landscaping ideas, so learning how to kill ants nest in lawn is pretty essential.

'Ants and their effect on a lawn can be a real nuisance, with their nesting and hills smothering grass plants and contributing to an uneven surface, at worst causing some yellowing from root damage,' says Jonathan Hill, Director and Lawn Expert, Rolawn. 'However, there’s nothing here that can’t be rectified.'

So you can get back to enjoying your garden ant-free, we've asked the experts how to kill ants nest in lawn, without causing any damage to your grass. 

Exterior of home with lawn, patio area, stepping stones and greenhouse

(Image credit: Future PLC)

How to kill ants nest in lawn

Whether an ants nest is ruining the look of your front garden ideas, or it's made an inconvenient home next to your back garden flowerpots, you need to know how to get rid of it. Here's how to kill ants nest in lawn, without hurting your well-kept grass.

What you'll need

1. Locate the nest

Large ants nest in forest

(Image credit: Getty)

The first step to learning how to kill ants nest in lawn is fairly obvious, but not always easy. You need to locate the nest to be able to get rid of  it. 

'Ants nests can be small and often hidden,' says Robert Collins, Pest Control Expert, MyJobQuote. 'Look for areas of the lawn where there is a lot of ant activity and from there, you’ll likely find the ants nest nearby.'

Even if there's a swarm of ants in one place, this isn't necessarily the location of the nest, so observe the ants for a while and see where they head back to.

Headshot of Robert Collins
Robert Collins

Robert Collins has worked as a professional pest control officer for over 20 years and has represented MyJobQuote as a pest control expert for over 4 years. Robert continues to provide pest control services in various regions across the UK, while also providing expert pest control advice on behalf of MyJobQuote. 

2. Apply a biological nematode

Close up of grass in garden

(Image credit: Rolawn)

Unlike learning how to remove weeds from patio, killing an ants nest in a lawn requires biological methods only, otherwise you risk damaging your grass beyond repair.

The experts recommend you use a biological, rather than chemical, pesticide, as strong chemicals like bleach can cause damage to other wildlife and plants. Biological nematodes are microscopic creatures that act as parasites on other insects, like ants.

'Nematodes act as an irritant and the ants are displaced from their colonies,' explains Jonathan from Rolawn. 'Lawns can be treated from April to October when the soil temperatures are warm enough for the nematodes to be effective.'

Look for the pathogenic nematode Steinernema feltiae, which is usually recommended for treating ant nests, though most ones that are suitable for killing ants will be advertised as such, like this Achat Nature Nematode, £11.75 at Amazon. Read the instructions that come with your nematode before applying. 

3. Dig up the nest

After you've applied a biological nematode, grab your shovel and dig up the remains of the ant nest. 'Make sure you dig up all the ants and eggs,' advises pest control expert Robert. 

It's probably best to throw the nest away so a new colony can't remigrate to the nest in a different location in your garden. Alternatively, you can bury the remains of the nest in a patch of public land. 

4. Prevent ants from returning

Lawn with plant border

(Image credit: Rolawn)

You've learnt how to kill ants nest in lawn, but it's helpful to know how to stop them from coming back so your efforts aren't wasted. Here are some expert recommended tips that will prevent ants from becoming a recurring problem in your garden:

  • Remove any food sources that might be attracting the ants
  • Use repellent sprays regularly to keep the ants away, like this Smart Spray Ants Away, £16.90 at Amazon
  • Brush or rake away disturbed soil after mowing the lawn, to prevent ant colonies settling

How to make DIY ant traps

If you've been looking into DIY ant traps recently, they can be a really effective method when learning how to kill ants nest in lawn. It's a fairly easy DIY project that doesn't require many supplies or much of your time. Try the method below as an alternative to a biological nemotade. 

What you'll need

1. Create your solution

To make your DIY ant trap, combine two teaspoons of baking soda with two teaspoons of powdered sugar. 

'Ants can’t differentiate between powdered sugar and baking soda as they are both similar in size,' explains pest control expert Robert. 'The sugar will attract the ants and the baking soda will kill them. Baking soda reacts with the acid in the ant’s digestive system and this is what kills them.'

2. Add your bait to the jar lids and place them in the garden

Garden from back of house

(Image credit: Rolawn)

Place the solution in the jar lids and leave these around the nest, or in strategic locations where you see the ants frequently. If you don’t have jar lids, you can place the mixture directly on the surface where you see the ants. However, be aware that it’s a very light powder so it could blow away before it has chance to work. 

3. And wait

Leave the bait traps in place for a few days and you should notice the number of ants reduce significantly. If the bait traps become quite full, you can empty them out and replace them with a new baking soda and powdered sugar mixture. 

Repeat the process until you stop seeing the ants, then dig out the nest and dispose of it.


How do I get rid of ants in my lawn without killing the grass?

DIY ant traps, like a solution of icing sugar and baking soda, are an effective way of learning how to kill ants nest in lawn, without damaging the grass. Contain a sugar and baking soda solution in a small container that the ants can easily access, like a jar lid. This will keep the ant bait off your lawn. 

You can also use pre-made ant bait. 'Ant baits are small, attractive pellets laced with poison,' explains pest control expert Robert . 'The ant will take the bait back to the nest and share it with the other ants, effectively killing the rest of the colony. These are a safe and effective way of killing the ants without causing any harm to your lawn.'

Alternatively, apply a biological nemotade, which will destroy the ants nest without damaging your lawn. Applying a nemotade can actually help improve the biodiversity of your lawn and support its ecosystem.

Why do I have so many ants nests in my lawn?

'Ants are attracted to sugary substances such as nectar,' says Robert from MyJobQuote. 'In addition, they collect seeds from plants such as radish, heather, viola, and cabbage, so if you have any of these in your garden, this could explain why there are ants nests in your lawn.'

'Ants also need water to survive so if your lawn is moist, it will be more attractive to the ants.'

If you've recently learnt how to make compost, keep this contained within a compost bin, as ants will be attracted to any lingering food scraps. 

Katie Sims

Katie Sims has been writing for Ideal Homes since spring 2022. She qualified from her Master’s in Media and Journalism in 2021 and has been writing freelance since. She has worked on Ideal Home’s ecommerce team where she researched the best home products on the market, and on the news team, researching the latest trends for feature pieces.