Which Bugs Are Good For Compost?

Ever since I started my vermicompost bin, I’ve noticed that quite a few different bugs have gradually found their way into it. Because of this, I had to move my compost bin outside. Still, I wasn’t sure if these bugs were good for the compost, so I did a bit of research to find out. Here’s what I found about bugs in compost piles and bins.

Insects like rollie pollies, worms, maggots, and cockroaches are good for compost. These bugs aerate the compost, eat its materials, and produce lots of droppings, which increase the speed that the compost decomposes. Also, small white bugs called mites can show up in the compost, but they do not hurt it.

So, exactly which bugs should be in your compost, and which ones shouldn’t? Why are rollie pollies, maggots, and cockroaches good for compost, and what about those white bugs? Let’s take a closer look.

Which Bugs Should Be in Your Compost?

Some of the most helpful bugs in a compost pile are rollie pollies, worms, and the larval stage of black soldier flies, more commonly known as maggots. While they might seem gross at first, these insects are an important part of the decomposition process and help your compost piles.

The most helpful insects found in compost piles include:

• Worms
• Rollie pollies
• Black soldier fly larva (maggots)
• Roaches
• Mites

Most of these bugs will be covered more in-depth later, but first, know that they speed up the decomposition of your compost pile by doing three things:

1. Introducing oxygen, which helps breaks down the ingredients of your compost. This also helps prevent mold and rot. Worms and maggots are especially good at this.
2. Eating larger pieces of organic matter, which can increase the pile’s temperature and make it decay faster.
3. Their excrement, much like animal manure, also increases the fertility and nutrition of the pile. 

So, while these bugs can be beneficial to compost piles, which bugs should not be in your compost?

Which Bugs Should Not Be in Compost?

• Bees
• Ants
• Houseflies
• Centipedes
• Spiders
• Slugs

Bees, ants, and houseflies are more of a nuisance than an actual problem, though some house flies can carry disease. 

These bugs are annoying enough to deter some people from turning their compost pile as frequently as they should, which can slow down the rate of decay and make it take much longer for the compost to break down.

On the other hand, centipedes and spiders are predators. They’ll hunt and eat the isopods and worms in your compost pile, reducing their populations and therefore, their benefit to the pile.

Slugs can eat large volumes of food, and they might hitch a ride from your compost over to your garden, where they will be happy to take care of all your lettuce and most of your other greens too.

Know that it’s unlikely you’ll be able to completely eradicate all of these bad bugs from your compost pile, but you can keep populations under control by keeping your pile slightly drier and adding a bit more brown matter such as leaves.

In contrast, let’s dig a little deeper into why bugs like rollie pollys and maggots are so good for your compost.

Are Rollie Pollies Good for Compost?

Rollie pollies (also known as sowbugs, woodlice, pillbugs, and isopods) are active bugs, which means that they provide a lot of aeration in your compost piles. They feed on rotting plant material and will go over, under, and through the compost, creating passages for oxygen to travel through and generating heat.

More oxygen and a higher temperature mean faster decay in general, so rollie pollies help speed up the development of your pile into finished compost.

Although they’re not technically insects, rollie pollies the only land-dwelling species of crustaceans.

However, these bugs are less beneficial in other areas in the garden, as they’ll hide in damp nooks during the daytime, but emerge at night to eat away at weak plants or root systems.

So, if you’d like to get rid of rollie pollies before you apply the compost to your garden, the most effective way is to let the birds pick through the compost and eat the bugs.

Spread some of your compost out in your chicken run and let them pick it over. Or do the same thing in an area away from your house where the wild birds will come down to feast. This is much more efficient and beneficial than picking through compost by hand.

So rollie pollies: good in the pile, less good in the garden. How about maggots?

Are Maggots Good for Compost?

Maggots are good for compost piles because, like other bugs, they provide a lot of aeration. Maggots are bigger eaters than isopods, so they aerate, consume, and break down more material. They also excrete more droppings. All of which are good for compost piles.

But not all maggots are created equal. Maggots are the larval stage of many different fly or beetle species. Some flies carry disease, and some beetles eat plants in your garden.

The best kind of maggot to have in your compost pile is black soldier fly larva.

These maggots are light beige to tan in color, with a segmented body, bristles, and grow up to ¾ of an inch long. They’re not pretty by any means, but they provide all the benefits of maggots in the compost pile without any drawbacks as adults.

The larvae of black soldier flies will generally out-compete the larvae of other, potentially more harmful, flies and beetles. Adult soldier flies don’t sting, bite, or carry disease, and they don’t tend to move into your home the way house flies or fruit flies will.

Even if your compost pile is full of black soldier fly larvae, most of them won’t hang around after they hatch.

To attract black soldier fly larvae to your compost pile, add nitrogen-rich materials like coffee grounds or fresh grass clippings to your pile. But do keep in mind that maggots also compete with worms, another beneficial insect that is not as big a fan of high-nitrogen materials.

Another unexpected ally in your compost pile? The humble cockroach.

Are Cockroaches Bad for Compost?

Cockroaches are detritivores, which means that they will eat almost anything. This is good news for your compost pile, because anything that the maggots, worms, and pillbugs don’t get, the cockroaches will take care of.

Wood roaches are the most common type of cockroach in a compost pile. They are smaller and more tan than the common household roach, and they have way less interest in invading your home. 

It’s best to relocate your compost pile away from your house or other structures if you find cockroaches in your compost, but wood roaches are unlikely to venture inside.

If you really can’t stand cockroaches at all, make your compost pile a little wetter or turn it more often. Roaches don’t like too much dampness or being disturbed.

Cockroaches will generally live in your compost while you are actively adding materials. Once the compost has broken down completely into humus, they will move along in search of other food sources—possibly to your next compost pile, or just to other likely spots in your yard.

What Are the White Bugs in Your Compost?

Mites are small white bugs that are drawn by the decaying matter in your compost pile. They’re beneficial to compost piles as they consume certain parts of the compost to increase the pile’s rate of decay. Mites are completely harmless to animals, plants, and people.

You may have noticed tiny white bugs in your compost. These are mites. While there are many different kinds of mites, these are most likely oribatid soil mites, also known as potting soil mites for their tendency to show up in that material as well.

The number of mites will decrease once your compost is finished breaking down, as there will be no more organic matter for them to break down.

While mites are harmless and even helpful, if they bother you, you can easily get rid of them.

You can reduce the population of mites by letting the pile dry out. You can also remove some of them by placing an attractive piece of food (like a watermelon rind) on top of the pile, waiting until it is covered in mites, and then removing it and immediately throwing it away. Some gardeners also place the food with mites on it in the cold or snow, which then quickly kills them off.