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Oh no!

You just saw a bunch of ants in your compost bin.

Are they going to harm the worms and your compost? You wonder.

Don’t worry. Ants are usually harmless and don’t affect your compost. But if you really want to get rid of them, here are a few effective methods you can try out.

How To Get Rid Of Ants In The Compost Bin

1. Keep a Lid On The Compost Bin

Your lid will not do much to physically prevent ants from moving in. The tiny insects can get just about anywhere!

But, the lid will keep the temperature in the compost bin high. Ants like warmth, but they hate excessive heat. Anything above 104 degrees Fahrenheit and they’ll move on to find somewhere else to live.

Heat is a natural byproduct of the composting process. The microbial breakdown of organic matter generates more heat than you think! A well-maintained bin can reach temperatures between 120 and 170 degrees Fahrenheit!

Usually, the heat escapes through steam in the cool morning air. When you keep a lid on the bin, the heat stays inside and keeps the compost at higher temperatures than ants can stand!

2. Add Moisture To The Compost

Ants prefer to live in dry soil. It makes things easier when the insects are tunneling.

If you have a large collection of ants crawling through your compost, it probably means that it’s far too dry.

Ideally, compost should have a moisture content between 40 and 60 percent. Add a bit of moisture to the pile and the ants should move out shortly.

Give the pile a few turns to ensure that the moisture makes its way to the middle of the pile.

Using Boric Acid and/or Diatomaceous earth is a great way of killing off ants safely and quickly from compost. Both substances are toxic to ants and will kill them if the ants are exposed. They are effective at removing an entire ant colony. One of the most effective ways to prevent ants from returning to compost is by using nematodes. These are microscopic worms that will deter ant nests. They are widely available, cost-effective, and considered safe. Other means of keeping ants out of your compost include regular compost maintenance; such as turning the matter regularly, raising the moisture level, and keeping it sufficiently warm. – Jesse, Founder, My Garden Flowers

3. Use Diatomaceous Earth

Diatomaceous Earth is a wonderful natural pesticide. It’s made of the fossilized remains of aquatic organisms called diatoms.

This simple powder substance can kill a wide range of pests. It does so by absorbing the oils and fats from the insect’s exoskeleton. Essentially, it dries the insects out.

You can use the Diatomaceous Earth safely. It’s organic and doesn’t come with all the risks that chemical products have.

The only problem with the pesticide is that it won’t target ants specifically. So, it’ll get rid of many beneficial insects, too.

The good news is that Diatomaceous Earth won’t harm your compost’s most beneficial bug: earthworms! Earthworms don’t have a tough exoskeleton, so they can stay behind and thrive. In fact, worms can eat this stuff!

4. Use Parasitic Nematodes

There are specific nematodes that will kill certain types of ants. So you can use those to control the ant population in your compost bin.

The problem is you need to first find out which ants are in your compost and then figure out the required parasitic nematodes.

You can purchase the parasitic nematodes from a garden center or some online stores.

To use the nematodes, you mix them in water and spray on the compost. The nematodes will enter the ant’s bodies and kill it.

The good news is that these nematodes are harmless to humans and other beneficial insects like earthworms.

I asked fellow gardeners what they used to get rid of ants in compost. Only 3% preferred to use pesticide. 50% were OK having ants in the compost. Some felt that the heat in the compost will take care of them. While 20% suggested using diatomaceous earth.

5. Use Coffee Grounds

Coffee grounds are a safe and effective ant repellent. The smell of the grounds will cause them to avoid the compost bin.

If you just have little coffee grounds, you can sprinkle it every few days on top of the compost. If you have a good supply, you can mix int into the compost. The coffee grounds are an excellent source of green material for your compost that is rich in nitrogen.

You could also add a few drops of essential oil, such as peppermint oil or tea tree oil, that acts as an irritant and causes the ants to move away from the compost.

6. Apply Chemical Pesticide

Using chemical pesticides isn’t ideal. However, it’s an effective last-ditch effort if other methods are unsuccessful.

If you want to use pesticides, stick to ones that have EPA approval for vegetable gardens. Carbaryl, pyrethrins, and spinosad are common ingredients that are safe if used correctly.

Carbaryl is moderately toxic and will kill any pests in the compost. But, it’s a good option if you’re dealing with fire ants. Just follow the instructions to ensure that insecticide has time to dissipate.

Pyrethrin is a much better ingredient. It’s biodegradable and doesn’t persist in soil. It usually breaks down within a few days in the sun.

Spinosad is organically acceptable and should not harm any crops or transfer to humans with proper washing.

If you’re composting in a bucket or tub or trashcan, the best approach is to apply some petroleum jelly to the edge of the tub.  The ants won’t be able to cross the petroleum jelly, which will create a protective barrier around the tub. If your compost is outdoors, and in a pile, it is more challenging..  You will need to apply a protective barrier of specific insect repellent that’s meant for outdoor use.  These outdoor insect repellent barriers can be hit or miss, so you may have to reapply it if the ants keep returning. But ultimately, creating a protective barriers is the best strategy to keep ants out of your compost zone. – Jeff Neal, Founder, The Critter Depot

How to Keep Ants Out of the Compost Bin

The best way to avoid ant infestations is to make your compost bin an unappealing site to call home.

If you’re doing things right, ants should never become a huge issue at all. The trick is to maintain the compost correctly so that it can break down efficiently without attracting too many unwanted pests.

Here are a few ways to keep ants out!

1. Keep the Compost Moist

As I mentioned earlier, moisture is important for your compost. It’s essential to the survival of all those beneficial organisms.

A good amount of moisture will keep ants out. When you check on the compost, feel it with your hands. It should be as moist as a wrung-out sponge.

The compost should hold its shape when squished into a ball.

There’s a fine balance between having too much water and not enough. As a good rule of thumb, compost with lots of green matter will need less water than compost with more dry matter.

Use your better judgment here and sprinkle the compost when you turn it to keep things moist.

Keep your compost bin or pile well-covered and moist, but not waterlogged. Ants are attracted to dry environments, so making sure your compost stays moist can help deter them. Make sure to regularly turn your compost pile. This will help to distribute moisture and heat evenly and can also help to deter ants. – Shalom Rosenbloom, Owner, Rosenbloom Pest Control

2. Turn the Compost Regularly

Speaking of turning the compost, you should do this often! Every three days is the best. How often you’ll need to turn the pile depends on its size.

Turning the compost keeps it loose and aerates the organic matter. Plus, it ruins any tunnels the ants have dug out! When you’re turning the pile every few days, the ants won’t have a chance to establish a colony.

3. Ensure The Compost Gets Sufficient Heat

If you have the right conditions in the compost bin, it will heat up to a good temperature between 120 and 170 degrees.

This is a good thing to prevent ants from making a nest in the compost because anything above 104 degrees is uncomfortable for them.

So ensure your compost bin has the right quantity of greens and browns. Add the required moisture and turn the bin regularly so the organisms can do their job and encourage heating in the compost.

4. Bury Food

Ants are naturally attracted to freshly cut fruits and vegetables. So, you want to mask those smells up as much as possible!

Burying food that you add will deter all kinds of pests, including ants. Not only that, but it’ll provide easier access for those organisms that want to break it down.

Surround the base of your compost bin with a layer of wood chips or straw. This physical barrier will make it difficult for ants to access the compost. If ants have already made their way into your compost, try placing a pie tin filled with a mixture of water and white vinegar near the entrance. The strong smell of vinegar will deter the ants, while the water will make it difficult for them to cross. Keep the area around your compost bin clean and free of food scraps or other potential attractants to minimize the appeal of your compost to ants. – Amber Noyes, Horticulturist, Ecologist, and Executive editor at GardeningChores.com

5. Add Natural Ant Deterrents

There are a couple of effective ant deterrents that you can add to your compost. These deterrents are all-natural, so they won’t affect the decomposition process.

The first additive you can try is eggshells! Eggshells are already wonderful for compost bins, as it adds calcium.

However, it also agitates ants! Sprinkle it around the pile to ensure that ants don’t move in.

Another thing you can try is ash from burnt wood. It’s a unique ant deterrent that can drive the pests away.

6. Use Aromatic Herbs In The Compost Bin

Finally, you can plant some herbs around your compost bin. Ants dislike herbs with strong aromas. It throws off their scent trails back to their colony.

You can plant things like spearmint, peppermint, catnip, sage, and more. The easier method would be to add a few drops of essential oil of these herbs into water and then spray that into the compost.

Are Ants in the Compost Bin Beneficial or Not?

Ants are still a point of contention in the gardening community. Some believe that they can be beneficial while others view them as major pests.

So which is it?

The truth is that ants can be a little of both.

The Good

On the one hand, the presence of ants can be a good thing. Ants, as well as other common pest insects, will still work their way through the compost to aerate it.

Ants are some of the finest earthmovers. As they tunnel through, they will shred the organic matter to bits and create pathways for air to move. Air is a must for odor-free decomposition, so ants can help in this regard.

They can also introduce other beneficial fungi and microorganisms into the mix. When they venture in and out of the pile, they’ll have some hitchhikers that will start improving the decomposition process.

Many ant species have a symbiotic relationship with fungi. The fungus relies the ants for dispersal and survival while the ants feed on the fungi. Those species can help your compost by diversifying the tiny ecosystem within.

Another big benefit of ants is their penchant for digging. Their natural tunneling does wonders to evenly mix the compost pile.

Often, compost piles unevenly decompose. This is because the organisms don’t have proper access to organic matter on top of the pile. That’s why turning the compost is so important.

While you’ll still need to mix the compost regularly, ants can naturally mix things up, too.

Finally, there’s the matter of nutrients. Studies show that some ant species can increase potassium and phosphorus levels in the soil. In controlled testing, the increase wasn’t minor. The ants provided substantial enrichment.

Compost is already very nutrient-rich. But the addition of potassium and phosphorus can make the finished substance even more fertile.

The Bad

While ants can do a lot of good, they’re largely considered unhelpful in compost piles.

Many lump them in with spiders, bees, centipedes, and other unwanted pests. Ultimately, ants do not help with the decomposition process. So, why let them live in your bin?

Ants go out to forage for food and bring it back to the colony. This doesn’t necessarily harm the compost. But, it doesn’t aid it either.

The goal with compost is to have beneficial organisms like earthworms, isopods, slugs, and fly larvae. Those pests will actively eat and break down the organic matter. Ants do not.

Another big problem is an aggressive ant species. While it’s rare, ants can kill the beneficial organisms in the compost.

There are several ant species lurking around your garden. You never know which ones are going to invade your compost, so it’s often better to deter them all to avoid issues.

Why Are Ants Attracted to the Compost?

No matter how big or small your compost bin is, it’s always going to be an enticing place for ants.

While you can take the steps, we went over earlier to deter them, compost naturally attracts ants. Here’s why.

1. A Warm Environment

In cooler temperatures, an ant’s body temperature will drop so much that they become sluggish. So, ants without a deep colony will seek somewhere warmer to call home.

All that organic activity in your compost bin raises the temperature dramatically. Like I said earlier, a properly maintained compost will be too hot for ants.

But it’s just right if you’re only getting things started. It takes several days for things to heat up to appropriate levels. Ants might move in during the meantime thinking that it’s a toasty place to hold out for the winter.

2. An Enticing Source of Food

Ants have four to five times more odor receptors than other insects. They’re attracted to all types of foods, including the stuff that’s in your compost.

When you toss fruit and vegetable scraps into your compost bin, you’re just inviting ants to take over! They’re particularly fond of sweet foods like fruits.

Once a worker ant finds your compost bin, they may signal the rest of the colony to move in. They’re highly opportunistic eaters, so they will often stay close to where food is.

What better place than a compost bin?

3. Wood and Water

Mostly, ants prefer dry soil they can easily dig through. But there are a few exceptions.

Some ants like moist environments filled with decaying wood. Sound familiar?

Small branches, dry sticks, and other dry yard debris are great for compost. However, it can attract Moisture Ants or Carpenter Ants.

Compost bins have everything these ant species need, so it’s not uncommon to see them invading even well-kept compost bins.

Can You Use Compost With Ants in It?

I don’t think there is any problem using compost for your plants if there are a few ants in it. They will probably move to another location that is convenient for them.

Even if the ants move around on your plants, they are harmless and won’t cause any damage to them.

I would not suggest using compost if there is a massive infestation of ants in it. You can get bitten when trying to use this compost depending on the type of ants.

Another problem ants can create is farming aphids on the plants. So ants won’t directly harm the plants, but aphids will. They suck the sap out of the tissue. The ants farm the aphids because they release a sticky substance called honeydew that the ants use as a food source.

What are the Different Ants You May Find in the Compost?

Did you know that there are over 12,000 identified ant species? There are nearly 1,000 in the United States alone.

Obviously, not all of those ants are hiding in your backyard. But, there are likely multiple species that will invade your compost bin. Some are going to be more invasive than others.

Here are some common species you might find in your compost bin.

Carpenter Ants

Indigenous to many parts of the world, Carpenter Ants love to chew on decaying wood. Most times, they can actually speed up the composting process!

But, they’re also known to eat earthworms.

Black House Ants

These ants look similar to Carpenter Ants. But, they’re more attracted to sweets.

This species is particularly dangerous because it can spread salmonella.

Harvester Ant

The Harvester Ant likes to feed on seeds. Usually, they prefer grass seeds. However, they’ll also consume seeds from fruits in your compost bin.

Odorous House Ant

Also known as the Sugar Ant, these pests gravitate towards sweet fruits and moisture. They can also consume dead insects.

Argentine Ants

Here’s a species that can multiply in numbers very quickly. They’re known to create super-colonies.

Not only that, but the Argentine Ant is very aggressive. It can attack defenseless organisms in your compost.

Fire Ants

Known for their painful sting, Fire Ants are a problematic species. For one, they’re very aggressive and can kill earthworms and other beneficial organisms in your compost.

Secondly, they can be difficult to remove after they have a sizable colony. Removing the ants may require extreme measures like boiling water or chemical pesticides.

Pharaoh Ants

Pharaoh Ants can feed on pretty much anything. They like dead insects, fats, and meat products.

Usually, those things aren’t found in a compost bin. But, the ants like humid conditions, which is common in compost.

This species has a complex foraging and reproduction process, so they, too, can be difficult to get rid of.

Here are some of my favorite container gardening tools

Thank you for reading this post. I hope it helps you with your gardening needs. I’ve listed some tools below that can help you with container gardening. These are affiliate links so I’ll earn a commission if you use them.

Gardening Gloves – I find the Pine Tree Tools Bamboo Gardening Gloves really good for both men and women. It’s made from bamboo so helps absorb perspiration. They are also comfortable and fit very well.

Containers – You know picking the right container is crucial for your container gardening. I’ve written a detailed post on the best containers you can choose from. If you’re happy with a plastic container, you can check out the Bloem Saturn Planter.

Watering Can – This is a must-have tool when you’re growing plants in pots or grow bags. It helps to water the potting soil without splashing on the foliage. The Kensington Watering Can is stylish, strong, and can provide precision when watering potted plants.

TrowelGarden Guru Trowel is my favorite because it’s durable and comfortable to use. My gardening friends really love having a trowel because they use it for digging soil, mixing fertilizer, moving seeds, leveling out the soil, mixing compost or mulch, and also dividing tubers

Bypass Pruner – I really like the Corona Bypass Pruner because it’s durable and gives a clean cut that helps plants recover faster. If you’re looking for something cheap, get the Fiskars Bypass Pruner that is really good as well.

To see an extensive list of the best container gardening tools gardeners recommend, check out this resource that I made for you.