Finding maggots in compost bins can be quite alarming for someone who just opened the lid or slid open the tumbler’s door. If this has happened to you, you might be wondering how to get rid of the maggots that are taking over your composting efforts.
If you notice hundreds—or thousands—of wiggly creatures in your compost bin, don’t freak out. As we’ll share later, maggots in the compost bin aren’t exactly a bad thing. In fact, they may be pretty helpful.
But if you don’t want to deal with maggots or flies at all, this article will help you out with that, too. We’ll cover everything you need to know about the new residents of your compost bin:
- What are maggots in compost?
- What causes maggots in compost bins?
- How to prevent maggots in the compost bin: 7 easy ways
- 5 tips on how to get rid of maggots in compost
- 4 FAQs about maggots in the compost
Finding maggots in compost buckets or seeing them take over your heap can certainly creep you out. They can be just as annoying as fruit flies! So we’ll explore why they’re ending up there in the first place, and what you can do to get rid of them.
To reduce your risk of pest infestations, you can always consider composting indoors too.
What are maggots in compost?
When you see something that looks like cream-colored chubby worms, you’ve likely found maggots in the compost bin. But what exactly are the maggots in our compost bins? Fatter than other types, maggots found in compost bins are typically larvae from the black soldier fly, or Hermetia illucens.
While they’re mostly an off-white or eggshell color, you may also see brown, gray, or white maggots. Their color variation is due to what they most recently ate, which is why some are darker than others.
You’ll know that they’re larvae of the black soldier fly by their length (usually around one-inch long) and the fact that their conical bodies are fatter than other types of larvae.
What causes maggots in compost bins?
Female black soldier flies look for warm, nitrogen-rich environments to lay her eggs. She’ll lay up to 500 at a time! Moist and abundant in nutrients, compost bins are perfect. Once the larvae emerge from the eggs, they’ll feed on the yard waste, food waste, and manure that we’re composting.
While it can be quite gross to find maggots in the compost heap or bin, it may not necessarily be a bad thing. If you’re providing things that flies eat and creating perfect conditions for black soldier fly larvae to thrive, you’re likely creating an environment suitable for quick decomposition.
However, we know that maggots may be unwelcome guests anywhere around the house—so let’s take a look at what to do about them.
How to prevent maggots in the compost bin: 7 easy ways
When it comes to how to prevent maggots in compost bins, there are a few simple things that can be done. Perfect for those just starting out with composting, you can consider the following methods while establishing a new composting system, or taking care of an existing one.
1. Keep your compost bin balanced
As we mentioned earlier, female black soldier flies look for nitrogen-rich environments to lay their eggs in. While composting systems require nitrogen to run optimally, adding too many nitrogen-rich components (i.e. kitchen waste and manure) can attract more black soldier flies.
Pro tip: Balance out nitrogen-rich additions with things like shredded paper, cardboard, leaves, and dry grass. If you can bury food scraps and add a two-inch layer of brown materials over your nitrogen sources, that’s even better.
2. Breakdown Food with Lomi
For a pest-free, maggot-free, odor-free solution, the Lomi is your food waste recycling solution. As a smart composter, it transforms waste into nutrient-rich dirt quickly and easily, which means smelly scraps won’t be sitting around to attract flies and their maggot larvae.
Pro tip: Do not leave unprocessed food waste in Lomi for more than two days. And if you add meat scraps or high-fatty foods to Lomi, make sure you run a Lomi cycle within 24 hours. Unprocessed waste should never be left in Lomi for too long.
3. Add grass clippings sparingly
Packed with nitrogen, there are few things flies like more than a mountain of fresh grass clippings. While it may be tempting to add an entire pile at once, thick layers of grass will be quick to attract black soldier flies.
Pro tip: Instead of piling the grass clippings on or dumping your lawnmower’s bag out immediately after it’s filled, take your time. Spread the clippings on in a thin layer, increasingly adding more over time. Or, let the clippings dry (and turn brown) outside of the compost bin before adding them.
4. Avoid composting fat, dairy, or meat
Generally recognized as harder-to-compost materials, meat, dairy, and fat take a long time to break down. While fruit and veggie scraps, garden waste, and coffee grounds will be processed relatively quickly, fats or animal products will take a while—attracting flies while they linger in your bin.
Pro tip: If you don’t have an electric food composter capable of breaking down meat, dairy, and fat, consider sending it to a commercial composting facility. If that’s not an option, consider leaving these out of the compost bin entirely.
5. Use a window screen
Most types of outdoor and indoor compost bins have holes to create the aerobic conditions that are often required. These holes can also be a way for adult flies to make their way into your compost bin to lay eggs.
Pro tip: If you want to stop maggots before they even get in your bin, use window screens to cover up the holes. Glue or exterior household caulk can be used to keep the screens in place.
6. Keep oxygen and moisture levels in balance
If you’re wondering how to prevent maggots in compost bins, one of the best things you can do is create unfavorable environments for them. Remember, black soldier flies and their larvae thrive in moist, nitrogen-rich environments. They also look for undisturbed environments in which to lay their eggs.
Pro tip: That said, turn the pile regularly to disturb its contents and speed up the decomposition process. Also, avoid adding excessive water, as too much moisture may create a smelly anaerobic environment that will attract flies.
7. Consider compost bins that are sealed
If you’ve been wondering whether a compost bin or pile is better for you, worries about maggots in the compost might provide your answer. While open composting systems may be a little more hands-off, closed compost bins are your best bet for protecting against black soldier flies (and their maggot larvae).
Pro tip: Instead of a compost heap, use a compost tumbler or another type of closed system. Just be sure to aerate the contents often so that you don’t get a build-up of moisture and heat.
5 tips on how to get rid of maggots in compost
What if you’re too late and already finding maggots in compost? If you’re wondering how to get rid of maggots in compost, you’re not alone. They may provide their benefits, but these weird creatures can be a little gross, to say the least.
- Add lots of carbon-rich material: Just like brown matter can be used to prevent maggots in compost buckets, it can also be used to get rid of those already in your compost bin. Wood chips, cardboard, shredded paper, and leaves can help to encourage the black soldier flies and their larvae to find a new home.
- Sprinkle on some vinegar: Thanks to its high acid content, vinegar can help to ward off maggots by creating an unfavorable environment. You can directly add ¼ teaspoon of vinegar for every 5 pounds of material you have in your compost.
- Carefully add agricultural lime: Adding lime (dolomite) is a great way to get rid of maggots in the compost bin—just be careful you don’t add too much. Lime can speed up the composting process, which leaves less food for the hungry black soldier fly larvae. However, adding too much can dangerously elevate the pH of your compost pile, which could actually slow the process down.
- Incorporate citrus fruits : While agriculture lime will make an unfavorable alkaline environment, citrus fruit will do the opposite. Adding orange, lemon, lime, and mandarin peels will create an acidic environment, which fly larvae don’t like either.
- Add pine needles: As another acidic material, pine needles can also help to keep maggots away. They might take awhile to break down, though.
Top 4 FAQs about maggots in the compost
Black soldier flies go from egg to adult in under 20 days. We’ll touch on some of the most common questions about their larvae so that you’ll become an expert in under 20 minutes!
1. Are maggots good for compost or bad?
Worms are helpful for compost and soil, so are maggots in compost ok, too? As it turns out, they’re better than “ok”—they’re actually pretty great for compost. If you can stand their appearance, sound, and smell, you might want to consider welcoming maggots into your compost pile, bin, or heap.
In fact, grub composting is the intentional use of black soldier fly larvae to transform green material and organic matter into grubs and compost. Like a worm farm, these systems use maggots (instead of red wiggler worms) to quickly break down the contents of your compost bin.
Not only that, but they also don’t carry disease. While biological control efforts may target other types of flies, the black soldier species is generally left out. They’re one of the few types of flies considered non-pests because they don’t transmit diseases or bite.
So yes, maggots in a compost bin can actually be a very good thing!
2. How do you reduce maggots in a compost bin?
While they may help to break down food scraps and lawn waste, having maggots in the compost bin may actually speed up the process too much. In the end, you could be left with sludge that’s lacking nutrients because they’ve all been consumed by the black soldier fly larvae.
That said, it’s a good idea to keep an eye on your compost to be sure that it’s not welcoming in too many maggots.
Remember, a single female will lay up to 500 eggs! Your bin may quickly become overwhelmed with maggots. If it does, consider adding more brown material, tossing in some citrus peels, or letting the compost dry out a little bit.
3. How do you get rid of maggots in a compost tumbler?
While compost tumblers are typically pretty enclosed systems, they often have holes that the black soldier flies can get into. If this is the case, consider using a window screen or mesh to cover up any entry points. Regular tumbling (aeration) and the addition of brown material will help, too.
If you have a tumbler that’s been overtaken by hundreds of maggots, you can also remove the compost and let nature work its magic.
Grab some rubber gloves and remove all of the compost (finished or not) from the tumbler. Lay it out on the ground and let birds eat the maggots. If you have chickens, the maggots will provide a tasty treat for them, too!
4. How do I prevent black soldier flies from laying eggs in compost?
A black soldier fly’s entire lifecycle is just 45 days long. If they’re in your compost bin, they’re definitely going to lay eggs. So, the best way to prevent maggots in your compost is by keeping the female flies out, so that they don’t even get the chance to lay their eggs in there.
Adding enough “brown” organic matter and layering it on top of your nitrogen-rich food waste will help to create unfavorable conditions for female black soldier flies.
To prevent them from entering, make sure that food and garden waste is covered by at least 2-4 inches of carbon-rich paper, cardboard, wood chips, and dried leaves.
As a recap, are maggots in compost ok? Yes, they’re actually a pretty good sign for your composting efforts. But, if you can’t stand their gross appearance (we don’t blame you!) you now know how to get rid of maggots in your compost.
If you want totally worry-free composting—like many other composters—you may want to use an indoor electric composter, as you’ll never have to worry about maggots in your compost bin.
Written by: Heather Seely