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The Kitchen Table

Pesky Fungus Gnats

18 years ago

Does anyone have these? I get these dumb gnats in my orchid medium. I thought I was just about rid of them, and now they must have hatched a new crop. Any ideas. I've got to new blossom stalks starting on one orchid, and am anxious to have some blooms, but those gnats drive me bonkers.

Leslie

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Comments (6)

paula_pa
18 years ago
I had these in my drains a few months ago. I cleaned the drains out really well and I put up a fly strip and I also put out a plastic container with vinegar and sugar in it, with small holes in the top to trap them. Eventually I got them all.
kioni
18 years ago
Grammahony, wander over to the HousePlant forum on the Garden web side, and search fungas gnats, there's been a couple of recent conversations on them, getting rid of them and prevention. They are supposed to look similiar to fruit flys, which get into our homes via fresh fruit like bananas. I use yellow sticky traps specially for them, sadly the local Wal*Mart has stopped carrying them. They are attracted to yellow, and this paper is really sticky, like fly paper, but it is a small card that is inserted in a stick that you prop in the soil near the plant, and as the adults fly into it they are caught and cannot get free to lay more eggs in your potting medium. Takes a while, since you have to wait for the eggs to hatch into flying bugs to also get caught in the trap. Their presence usually means a plant has been kept too wet and some of it's roots have died (and that doesn't take long!) and that's what the larvae feed on it the dead and dying plant matter. And they love to fly in your face!

Happy Bug Trapping!
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kathi_mdgd
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I had them for awhile on my bay window where all my african violets live.I kid you not,i'd get up in the morning and it looked like black carpet.I lightly sprayed them,only to have more be there the next morning.So i moved all my AV's out of the way and i saturated the windowsill and let it set for a couple minutes,then mopped up the excess with a paper towel.Then for a few more mornings i would find dead ones on there.The spray worked and is still working and it's been over a year since i sprayed.

I know because every once in awhile i'll see a couple but they will already be dead.

I just used regular old Raid.
Kathi
gardenspice
18 years ago
Hmm, with an orchid it is a little tougher, but if you let the soil/medium dry out, that will get most of them.
Also, a shallow bowl of cider vinegar will attact them. For some reason, they fly in and drown.
oscarthecat
18 years ago
Cover the medium with a layer of fine sand about 1/4 inch deep. Steve in Baltimore County.
grammahony
Original Author
18 years ago
I put the brown (cider) vinegar out last night. I put Saran Wrap over it, and poked a few holes in it. They say the gnats are to dumb to find their way out, after once flying in. But, they haven't flown in yet. I've also heard of putting Vaseline on a yellow piece of paper, and catching them with that. I don't have any Vaseline right now.
The Orchid medium is to stay kinda moist. Well, dry out between waterings.
Thanks for your help. I'll wander over to the Orchid area. Maybe someone there has some ideas too.
Leslie

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