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Tons of flies in my compost tumbler?

I have a double-sided compost tumbler that I use. I know those are generally not best practice but it's how I needed to start (small, contained) and it's mostly been working for me. I got a couple of really good batches of compost out of last summer (my first year) and one this spring after the winter thaw.

However, now I seem to have flies. Not fruit flies, but little flies. Every time I open the bin to put more scraps and leaves in, a swarm of flies come out and attack me. I didn't have this last year! Help!

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Re: Tons of flies in my compost tumbler?

no big deal imo. flies are decomposers. they are just speeding things along

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Re: Tons of flies in my compost tumbler?

How "little"? Could they be Black Soldier Flies?
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Re: Tons of flies in my compost tumbler?

rosiegirl wrote:... I didn't have this last year! Help!
I also don't think it's a problem. The reason you didn't have it last time is probably because you didn't have the habitat, but now you do. I also noticed after I started composting (and gardening) that every year I seem to get a new population of animal attracted to my habitat.

One of the first things I got was an invasion of snails/slugs feasting on all the mulch and new plants I provided; I had so many that they were climbing on my walls of the house, especially after a rain. This was also why I could not grow hostas, they'd be eaten up within a month.

That only lasted a year, because other things moved in that knocked their population way down, such as the legless lizards and I have tons of moles. It's actually quite uncommon for me to now see a snail and I haven't seen a slug in years. They're out there, but if I want to see them I have to go looking.

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Re: Tons of flies in my compost tumbler?

Umm ... by no stretch of the imagination could I call black soldier flies "little" ! :)

If you want to cut down on the flies, cut down on the moisture. If you let your stuff in the tumbler dry out a little more, it may not compost quite as quickly, but it will be less hospitable to lots of different kinds of larvae. For right now, you can accomplish that just by throwing a bunch of extra browns (fall leaves, straw, shredded paper, etc) in and mixing them. They will absorb the excess moisture. (You do know about balancing "greens" and "browns," right?)

I have never had a tumbler, but from all the people who have written in here about them, it seems like they are prone to excess moisture, not draining well enough and sometimes getting stinky from combination of excess moisture and not enough air circulation. You can help with all of these issues by putting more air/drainage holes in it and then being sure you do spin it frequently (and keeping your balance a bit heavier on browns than you might with a compost pile on the ground and un covered).
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Re: Tons of flies in my compost tumbler?

You can also leave the door open (ONLY in dry weather!) to give it a big hole for excess water vapor to escape.

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