Ants In Compost Pile – Should I Worry?

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In Brief: Ants In Compost Pile – Should I Worry?

Finding ants in the compost pile does not necessarily mean that you should worry. Ants are part of the composting process, introducing certain microorganisms to the pile. But in some cases, they can cause a few issues when it comes to the health of your compost pile. Here is how to know when to worry and when not to.

Sometimes, ants can be a good sign when they populate the compost heap.

One reason is that they also bring fungus and other microorganisms that will enrich the compost in potassium and phosphorus.

On the other hand, if you notice numerous ants in the pile, it can be detrimental to the health of your yard. This is because ants often protect the aphid populations on the plants nearby.

Why Do Ants Go To Compost Piles?

One reason why ants might overpopulate the pile is if the food materials are exposed.

In order to control the population, it is recommended to turn the compost frequently by putting the outside materials in the middle of the heap. This should be at least every 2 weeks.

Furthermore, numerous ants on the heap are also an indication that your compost pile is too dry. If this is the case, you can sprinkle some water to add moisture.

However, make sure you do not soak the pile as this will cool down the temperature and slow the composting process.

If you have a problem with fire ants in your compost heap, take a look at this video to get a few tips on how to get rid of them:


The right level of moisture is when the materials look like a wrung-out sponge.

If you are unsure, take the materials in your hand – they should form a ball when they are squeezed, with a few drops of water dripping out.

Sometimes, the pile might remain dry even if it is watered regularly.

This can be the case if the water does not get inside the pile; in this case, you can add water on each layer rather than sprinkling only overhead.

When you make the compost, you should always check that the woody parts and plant debris do not have ants, as you will introduce them by mistake into the compost.

Furthermore, if the temperature is lower than 140F, this might explain the ants.

It is important to ensure that the temperature is high enough, which will also speed up the process. It is best to use a compost thermometer for this step.

As ants and other insects prefer dry, cool environments, you can cover the heap with a plastic cover, keeping it both warm and moist.

This will reduce the ant population or eliminate it completely. It is important to keep an eye on the compost at this stage.

When the temperature is between 140F and 160F, you need to uncover the pile in order to allow for good air circulation.

The lack of oxygen is detrimental to the composting process, so this method is only for temporary use.

If you still have worrying populations of ants, you can purchase parasitic nematodes from garden centers and apply them to the compost in spring

. These are microscopic worms that attack ants and keep them out of the compost pile. Parasitic nematodes are not harmful to children, plants, or pets.

You can also watch this video to learn how to get ants out of your compost pile:


All in all, ants in the compost pile should not be a cause of worry.

If their numbers are high, it is a strong indication that there is something missing from the compost pile – moisture or a high temperature. These can slow down the composting process.