black soldier fly maggots

Maggots In The Compost, Are They A Bad Thing?

Maggots – yucky, right? Maggots are the larval stage of the life cycle of most types of flies and usually indicate that something somewhere has gone bad. One fly can lay tens or hundreds of eggs that, in a few short weeks, can become hundreds of adult flies. If you find maggots in the compost heap you have in your yard, it may be pretty shocking, but before you go wild and throw out the whole heap, there are things you should know about maggots in the compost.

How does a compost heap work?

Before you panic about maggots in the compost, we should lay out how your compost heap goes about turning plant matter into rich, dark soil.

Supplying a pile of organic materials with water and oxygen will result in that material beginning to break down. This process is helped along by useful bacteria and other things that live in the compost heap. Over time, all of the activity in your heap will warm it up, which further helps the organic material break down.

Composting doesn’t happen all by itself! It needs countless tiny little critters to help break it down, including flies.

What lives in your compost?

There are lots of different microbes, insects, worms, and other creepy crawlies that are highly beneficial to your compost. Creatures you might find living in your compost include:

  • Microbial life, like bacteria and fungi
  • Nematodes
  • Mites
  • Worms
  • Various flies
  • Snails
  • Slugs
  • Woodlice (pill bugs/rolly pollies)
  • Beetles
  • Flatworms
  • Ants
  • earwigs
  • Beetles
  • Centipedes
  • Occasionally larger animals

Each of these creatures plays a role in breaking down organic matter and will help your compost along, although to you or your neighbors, some of these creatures may be considered pests.

Read More: Can You Compost Tea Bags? It Depends

Are maggots in the compost bad?

black soldier fly

Answering the question ‘are maggots in the compost bad’ requires you to define what bad is, exactly. Not every fly is considered a pest. For example, black soldier flies, whose adult forms (pictured above) do not readily spread disease or bite because they don’t eat, are harmless and not a nuisance at all. Fruit flies or house flies are another story.

It is generally our recommendation to not panic over maggots in your compost and let nature take its course. There are some things you can do to reduce or eliminate maggots in the compost.

Add lime

Compost doesn’t need lime to break down and it can increase the pH of the soil your compost produces, so beware. But lime can deter flies and reduce the presence of maggots. Just add 1 cup of lime per 25 cubic feet of compost. You can also add pine needles or citrus fruit peels for the same effect.

Keep Reading: Is It Safe To Pee In Your Compost?

Add browns

Maggots feed on food material, like spoiled fruits and vegetables. They don’t generally feed on ‘browns.’ Browns are pretty much any brown material that you would clean up in your yard. Think straw, grass, leaves, etc. Maggots don’t eat browns and browns can help dry out your compost.

Seal up your compost

Compost needs oxygen in order to break down. Otherwise, all the little bugs responsible for your compost turning into soil won’t be able to thrive and do their thing. That doesn’t mean you need an open-air compost heap. You can build a container for your compost that has tiny holes and get about the same desired effect. The tiny holes will allow fresh air in, but will be too small for larger insects, like flies, to get into.

So you have some options for maggots in your compost but, to reiterate, we generally recommend leaving your compost to its devices unless it’s producing a large number of nuisance insects or animals.

Keep Reading: How Long Does It Take To Make Compost?

Cody Medina
Small Scale Farmer
Hi there! I'm Cody, a staff writer here at The Garden Magazine and a small-scale farmer living in Oregon. I've been gardening most of my life and now live on a quarter-acre farmstead with chickens, ducks, and a big garden.