Ugggh, fruitflies/gnats! - Page 2 - Orchid Board

Ross · #11 09-30-2007, 06:53 PM

I need to jump in and say that some of us get the fungus gnats in our orchidariums on mounts due to high humidity (90%+) and mounts, where orchids aren't changed about any time soon. So, there is a list of cures that does not involve replacing mix, as there is no mix to speak of. Just so we are all clear on this

Tindomul · #12 10-01-2007, 12:13 AM

Over watering perhaps? I often get lots of fungus gnats when i over water new plants/newly potted plants. Again, having to do with fungus in the media.

solo1979 · #13 10-01-2007, 12:18 PM

Now that makes sense Ray. Don't want to jinx myself, but the flies seem to be disappearing.

Tommyr · #14 10-01-2007, 04:28 PM

Since the larva are in the soil mix maybe a drench with some soapy dishwater will help kill them.

solo1979 · #15 10-01-2007, 04:54 PM

When I had a bad case of them, it's cuz the media was staying too wet. But now, I really don't think I'm overwatering. If it has to do with fungus, maybe a spray of Physan 20 on the mix will help. I could try the soapy water too. Will assess the situation again when I get home.

Ross · #16 10-01-2007, 05:25 PM

Quote:

Originally Posted by solo1979

When I had a bad case of them, it's cuz the media was staying too wet. But now, I really don't think I'm overwatering. If it has to do with fungus, maybe a spray of Physan 20 on the mix will help. I could try the soapy water too. Will assess the situation again when I get home.

Physan 20 would help hold back the fungus, but not the gnats. I traced my source to one particular mount and sprayed the whole root mass with Garden Safe insect spray (safe for household use.) That and the yellow sticky strips broke the cycle nicely. Unfortunately, there's no easy way to "refresh" the media on a mount

solo1979 · #17 10-01-2007, 05:27 PM

Thanks Ross. I have some insect spray for indoor plants too, but when I tried that last month it didn't seem to affect these guys. For me, they have just sort of came and went when they pleased. I just got nervous thinking maybe this time they'll want to stick around, now that I have the humidity trays in place with a constant source of water. Hope not. Will keep everyone posted.

Ross · #18 10-01-2007, 05:33 PM

Quote:

Originally Posted by solo1979

Thanks Ross. I have some insect spray for indoor plants too, but when I tried that last month it didn't seem to affect these guys. For me, they have just sort of came and went when they pleased. I just got nervous thinking maybe this time they'll want to stick around, now that I have the humidity trays in place with a constant source of water. Hope not. Will keep everyone posted.

The spray was not so much for the flies themselves which are just as inocuous as fruit flies, but for the teeny white worms which are the real problem guys. You can spray down the medium and pots with the insecticide (if it's a safe one for indoors) and then hang some flypaper-type strips to catch the adults which are trying to mate and lay eggs. They are most attracted to yellow color, thus the yellow paper strips that are so common.

gmphoto · #19 10-15-2007, 11:53 PM

I've gotten fungus gnats from various plants that have low grade soil. To get rid of the gnats you need to treat the problem. Fungus gnats will lay their eggs in the soil so insecticide needs to be used. I've used Safer soap and just doused the soil. Works like a charm. To prevent them from coming back be sure to avoid over watering. Hope this helps!