Help! Maggots in My Compost!
We've had a flurry of questions over the last couple weeks here at Gardenerd.com. Here's one that came in with urgency:
"We have had an issue with maggots in my compost tumbler. I am not using any meats or fats of any kind - only green food wastes. How do I correct this? Is my compost ruined?"
Not to worry. Those maggots (most likely Black Soldier Fly larvae) are actually helping your compost break down. While it's true that they bring out the "ick" in most people, maggots, worms, and other garbage consumers are actually powerful creatures when it comes to ridding the world of waste. Here are a couple articles that I found to ease your mind:
Turn your pile - keeping air flowing through your pile will help in every way. Turn your pile often (letting it get hot in between turnings) and that should help.
Watch the water - compost piles need to be wet, but not too wet. Too much moisture creates an anaerobic environment, which can cause that rotting smell of garbage to permeate your world. The general rule of thumb is to keep your compost pile "moist like a rung out sponge."
Hope this helps. Keep us posted on the activity in your compost pile.
"We have had an issue with maggots in my compost tumbler. I am not using any meats or fats of any kind - only green food wastes. How do I correct this? Is my compost ruined?"
Not to worry. Those maggots (most likely Black Soldier Fly larvae) are actually helping your compost break down. While it's true that they bring out the "ick" in most people, maggots, worms, and other garbage consumers are actually powerful creatures when it comes to ridding the world of waste. Here are a couple articles that I found to ease your mind:
Big maggots in your compost - from Oregon State University
Always end with brown - Now, if you still don't want these critters in your compost bin, one thing you can do to help ward them off and keep them away is to make sure you have a thick enough layer of "browns" - i.e. dried leaves, shredded newspaper, dried grasses, etc., on the top of your pile.
Yucky but useful -this is a fun one from San Francisco Gate (Chronicle)
Always end with brown - Now, if you still don't want these critters in your compost bin, one thing you can do to help ward them off and keep them away is to make sure you have a thick enough layer of "browns" - i.e. dried leaves, shredded newspaper, dried grasses, etc., on the top of your pile.
Turn your pile - keeping air flowing through your pile will help in every way. Turn your pile often (letting it get hot in between turnings) and that should help.
Watch the water - compost piles need to be wet, but not too wet. Too much moisture creates an anaerobic environment, which can cause that rotting smell of garbage to permeate your world. The general rule of thumb is to keep your compost pile "moist like a rung out sponge."
Hope this helps. Keep us posted on the activity in your compost pile.
Posted by Christy Wilhelmi at 3/11/2009 8:25 AM 
Categories: Sage Advice
Tags: composting flies in compost maggots in my compost compost pile maggots
Categories: Sage Advice
Tags: composting flies in compost maggots in my compost compost pile maggots
thanks for your prompt response to my question! i really enjoy your website and i have followed many of your suggestions.
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thanks for your prompt response to my question! i really enjoy your website and i have followed many of your suggestions.
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I know there is already a thread about maggots in compost, but I have a few questions. I wasn't purposely trying to attract them to my pile, but they sure found it. All I have in my bin are grass clippings, oak leaves, food scraps(no meats or grease), newspaper and various other paper products. I read the article that was posted about them being beneficial, but just want to make sure that its safe....cause I plan on eating the Veggies I grow with this compost. I guess because of their diet, my mind jumps straight to "Disease." So I guess what I'm asking is: Are they actually clean, despite the fact that they love to eat the dead and....poo?
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Not to worry. As far as I know, maggots are not going to harbor any diseases in your compost bin or finished compost.
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I've read quite a bit today and it seems that even if you have a "dry" pile you still get flies - BSF or house. In theory I don't have a problem with a few... but I do have a problem with a lot... because if I'm not mistaken those suckers are eating my dirt! I know they output (like earthworms) but I'm not sure their output is what I want... especially since the pile keeps getting wetter without me adding wet stuff... the larvae are producing their own liquids... which makes this an uphill "browns" battle! They do eat a lot and FAST.
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Aww, this was a really quality post.
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Good read. There is currently quite a lot of information around this subject on the net and some are most defintely better than others. You have caught the detail here just right which makes for a refreshing change – thanks.
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This article is great, thank you very much for sharing
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I do wonder about the liquid the BSFs secrete. Would this be good for watering plants as well? Are there any nutrients in those (like compost tea)?
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That's a really good question. The only thing I've seen written about them is their voracious appetite that helps devour food scraps more quickly in the compost bin - things like cheese and stuff that you're not really supposed to put in there. In the end, it all gets mixed together as organic matter, so I'm sure it can't be all that bad.
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Well I guess I'll just have to experiment and find out. But where do I get my hands on some BSF...
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hi Christy, i'm a neighbor in Mar Vista and have LOTS of BSF larvae in my compost tumbler, and they've made my compost wet. and icky. really icky. it moves. i'd say there are hundreds of these worms. i've seen a few of the flys. my understanding is that these worms are all going to hatch at some point? yikes.
what to do??
FWIW, i just googled my problem and come up with a great thread from you, our neighbor, on gardenerd. how neat! thank you in advance for any help or suggestions.
kiki
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HI Kiki,
The Black Fly larvae are in my worm bin as well. They will hatch into flies and leave eventually. It's the time of year for them I guess. Gross, yes, but they do help break down the waste material. If you wanted to scoop them out, you could, but I'd just leave it and let nature take it's course.
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Hello -
I put a cantaloupe rind in my compost bin last night and this afternoon it is teaming with giant caterpillar size maggots - all attacking the rind with gusto. Is this ok? Every so often we leave the bin lid up to air it out as we don't have quite as many leaves/brown material as necessary. So I imagine the flies got in there and laid. But it's so gross to see them over night! Is something wrong? Should I be concerned?
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Hi Em,
Sounds like you have black soldier fly larvae in there. 'Tis the season. They are fine to be in your bin, as they consume a tremendous amount of food waste. While it's true they are gross, as the blog mentions, they help your compost along. If you really don't like them, you can scoop out the larvae, but it's pretty tough to get rid of them entirely.
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