Are Maggots in Compost GOOD or BAD?

Are Maggots in Compost GOOD or BAD?

You recently reached into your compost bin and discovered a lot of maggots in your compost pile. This has left you wondering whether or not your compost is ruined. Questions like ‘What do I do now?’ ‘Are maggots in compost good or bad?’ ‘Can I still use it?’ are probably running across your mind.

You’ve sampled the opinion of your neighbors and still haven’t gotten a satisfactory answer. Well, the truth is, maggots in compost are beneficial but only to a certain degree. A massive infestation will see your compost have little or no nutrients. Other than that, maggots in compost are largely beneficial.

In this article, we will explain what these maggots are, its common causes and even proffer solutions to rid you of them if they gross you out.


What species of flies are in my compost?

If you have a compost bin or a garden of your own, you’ve probably come across greyish-brown larvae in your compost pile. These maggots are known as Black Soldier Fly Larvae (BSFL).

They are found mostly in manure, outdoor toilets, compost and the tropical/subtropical Western Hemisphere and Australia. They can also be seen in bright areas, resting on vegetation, nearby structures, as well as flowers of the carrot and daisy families. They are one of the most beneficial flies and have been termed the new superstars of sustainable aquaculture.

An adult black soldier fly does not possess a mouth part, does not bite and it’s incapable of feeding upon waste. The larvae, however, are scavengers that thrive on decomposing organic matter, algae, compost heaps, manure, carrion, and plant refuse. BSF eggs incubate between four days to three weeks before hatching. Once hatched, the larvae are about 0.07 inch long and has an off-white color.

As they mature, black soldier fly larvae become reddish-brown with darker rings around the body segments. They are capable of eating twice their body weight daily and converting vegetable waste into little fat bodies containing up to 35% fat and 43% protein.

This makes the larvae a nutritious food for chickens and birds. It can also be dried and used as food for fish and exotic pets.

Are there other species in my compost pile?

Although the housefly larvae and other types of worms can be found in a compost pile, black soldier fly larvae are the most common. This is because the black soldier fly will protect its nest by fighting off other insects. Also, compost is a natural pesticide for these other flies.

Common causes of maggots in compost bins

Now that you know what those maggots here, you are probably curious as to how it found its way into your compost pile. Well, here’s the answer.

Food waste is the primary cause of maggots in compost. Because black soldier fly (BSFL) are so efficient in breaking down food, they run out quickly, therefore, BSF tend to lay their eggs in decomposed organic compost, manure, or places with enough waste.

BSF’s preference for warm environment and the right amount of humidity, in this case, moist food waste will see it lays its eggs in vegetable matter with high water content, therefore, finding a balance between green waste (vegetable matter) and browns, which include potatoes, wood chips, hay, and other dry vegetables is very important when layering your compost.

Not turning or mixing your compost pile often can be another cause of maggots in your compost. To prevent warmer center and cooler edges at the center or bottom of your compost bin, be sure to mix up your tumbling composter or open-air compost with a pitchfork or shovel every day. Continue doing this until the larvae die. When the flies have moved on, or the air cools down, reduce the raking or mixing to twice a week.

However, you should be careful not to dry it out completely.

Is it okay to have maggots in my compost?

Yes, it is okay to have maggots in your compost. Those little buggers are extremely quick and efficient in breaking down food waste, turning it into a form that’s easier for other worms to digest. As long as the environment is warm and comfortable, black soldier fly larvae (BSFL) will process compost faster for you in a matter of days. Sounds unbelievable, right?

They can also be a great food source for your chickens, pets or other animals on your property as it is a good source of protein. Chicken and pets, for example, may like to hunt for black soldier fly larvae when your compost is finished. They can also break down manure into component parts, and reduce the chance of diseases in areas where animal waste is stored.

While black soldier fly larvae (BSFL) is largely beneficial, too much of it may destroy your garden, leaving it with little or nothing in the way of nutrition. Once again, finding a balance is very essential.

Are maggots bad for my garden?

No. Maggots are not bad for your garden. It is neither harmful to you or your plant. If your compost is distributed amongst your garden plot, you would most likely turn in those maggots as well. Many would eventually grow into adults and fly away, while others may suffocate, providing nutrition for the soil.

How do I kill maggots in my compost bin?

Solution 1: Do not allow flies in your compost tumbler/ bin

Let’s face it, the only way maggots can find its way into your compost is if an adult Black Soldier Fly lays eggs. While your compost needs good airflow, make sure there aren’t any huge holes for the flies to enter and exit from. Check for holes and cover them with mesh screens to stop more eggs from being laid.

Solution 2: Layer your compost correctly

Another great way to get rid of maggots is to layer your compost correctly from the start. To do this, start with a layer of brown waste, preferably a 6- inch layer at the bottom of your compost bin. Leave six inches between the brown waste and the sides of your compost bin. Horse manure is the best source for brown waste, but dried leaves, shredded newspaper, straw, shredded cardboard egg cartons, and even sawdust also make good brown waste material.

Next, add a layer of food waste (coffee grounds, eggshells, flowers, cooking scraps) and another 6-inch layer of brown waste that will extend down into the space between the bottom layer and the sides of your compost bin, while covering the food. Doing this will prevent any odor and seal off the food layer.

Solution 3: Add lime or vinegar

Adding lime or vinegar to your compost is another great way to get rid of these maggots. The problem is that your compost may have a high PH rate after adding any of the above. Another issue is the risk it poses to the microbes involved in breaking down your compost. These microbes need nitrogen to function and adding lime or vinegar will only make them get less.

Add a tablespoon of vinegar per 20 pounds of compost to deter flies.

Solution 4: Turn your compost regularly

Turning the heap severally will get rid of the maggots. To redistribute nitrogenous rich portions and oxygenate the less rich portions, compost heaps need to be turned regularly. It will also break down larger high carbon elements.

Let your compost be

You may really dislike the sight of those wigglers and have probably tried every tip out there but you can still find them in your compost bin. You are wondering if there is any other solution out there. Then it’s time to let it be. Stop worrying. As long as your compost is processing nicely, there is nothing to fear. There is really nothing wrong with seeing maggots in compost. It’s all part of a process. Your compost will most likely turn out fine. Maggots in your compost pile aren’t the end of the world. Even if they are still present when your compost is ready, you can still make use of them.

Other tips

  • In place of vinegar, you can also use pine needles or citrus fruit waste.
  • Although compost piles need to be wet, too much moisture may create an anaerobic environment that can cause the pungent smell of garbage. It is that smell that attracts flies.
  • Another easy way to get rid of the maggots is by spreading your compost and allowing birds to pick out the maggots. You can gather it back into the bin afterward.


The verdict is, there’s not so much to get freaked out over if there’s only a little cluster of maggots in your compost. If anything, they prove the heap is decomposing nicely. Maggots would only thrive where there is nutrient breakdown.

However, when they are all over the place and making it difficult to monitor the progress of your compost, they’ll become a problem. Hopefully, this article has given you all the tips you need to set your composting straight with maggot trouble.

Happy gardening!