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Looking for non-toxic, indoor plant remedy for gnats/flies

17 years ago

I've noticed an ever increasing population of what I can only describe as gnats or small flies hanging around our indoor plants. Mostly in the upstairs bathroom where we have three of them but elsewhere around the house where we have plants as well. We have a 5 month old so the last thing that I am doing is spraying anything even remotely close to a chemical in the house. I'd sooner toss all the plants outside for the winter, but I don't want to go that route either. Any suggestions as to a non-toxic, preferably natural indoor plant remedy for getting rid of these annoying bugs? Thanks in advance.

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Comments (5)

jean001
17 years ago
They're fungus gnats and they're thriving because the potting mix is too wet.

You can do one or more things, all non-toxic:
1. Allow the surface of the potting mix to dry before you water again.
2. Remove and replace the top 1/2 inch of potting mix.
3. Get some Gnatrol, usually used against mosquitoes but also effective against fungus gnats, dissolve in water, then use that to water your plants.
embee
Original Author
17 years ago
A belated thanks for the reply. You know the very topic of "insecticides" just scares the you know what out of me where newborn development and the like are concerned. It's just not a good combo, all the baby books clearly state no way no how just say no. So I'm nervous about using any chemicals whatsoever around our baby, even though this Gnatrol sounds more like a "biological solution" versus a traditional insecticide or pesticide. I've read the label and warnings, not entirely convinced of its non-toxic status but it is what it is. I'll probably call the company directly as well later today, but I did order a quart. The plants around the house are no where near where the baby is or could wind up, so it's really up to me, how I use it, how I make sure to clean up everything including myself after the fact, etc. Thanks again, if you want to weigh in on the non-toxic topic here just to calm my nerves, I would be most appreciative :)
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rhizo_1 (North AL) zone 7
17 years ago
Do some reading regarding Bacillus thuringiensis and you will be able to put your mind at rest. Bt is simply a naturally occurring bacterium that has been used commercially for 50 years in the control of specific pest insects. The strain of Bt that is in Gnatrol controls the larvae of insects within the Diptera order....flies, gnats, mosquitoes, etc.

Just as your fungus gnats cannot contract human diseases, humans cannot be affected by B. thuringiensis. If that were the case, we wouldn't be here. This bacterium is ubiquitous in nature.
webkat5
17 years ago
I have found fungus gnat larvae further down than 1/2 inch in my seedling pots. If you allow all of the soil to dry, they will die.
This is the only way to eliminate the problem without any kind of chemical at all.
jean001
17 years ago
As was said, allow the surface of the potting mix to dry before you water again. The population will decline and you needn't use anything you consider nasty.

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