How to resolve gnat issues - Orchid Board

Paul Mc · #1 02-19-2011, 09:31 AM

Well, I guess it must be the time of year because suddenly there are lots of gnats appearing in my windsills. I've installed some Black Flag window traps, but after having done some reading I'm concerned about the babies eating the roots of my orchids. What can be done to get rid of these pests?

I've read one place that using something like sticky traps can be used, but then I might want to consider using mosquito dunks in the water I water with as well to kill the larvae and eggs.

Any thoughts and suggestions?

Eyebabe · #2 02-19-2011, 09:33 AM

I use the dunks/mosquito bits in the water and I no longer have a problem with gnats

That's for the larva...if you want to kill the "current living adults" you can also spray with some Neem Oil...

Paul · #3 02-19-2011, 10:19 AM

Unfortunately, I have not found the mosquito dunks to be effective. I am currently trying the dunks in the water I use for my terrariums, but have not seen any decrease in the fungus gnat population.

johnblagg · #4 02-19-2011, 10:26 AM

the yellow sticky traps are used in commercial greenhouses a lot for this ....I use black flag no pest strips hanging among my chids ....LOL bragging just a bit but I have no bugs of any kind while indoors in winter...I also use the Bayer 3 in one product a couple of times when They come inside and once mid winter....
I also have to credit s/h for really making bug problems minor as welll

stefpix · #5 02-19-2011, 12:55 PM

I grow some Mexican Pinguiculas. Gnats are attracted and the problem is solved

RosieC · #6 02-20-2011, 05:28 AM

I have some sticky traps, which are catching some, but they are still about. Definately reduced the numbers though.

I also find that leaving a glass of half water half sprite (or other clear lemonade) amoungst the plants catches a lot. They just seem to drown in it

I've not done anything to kill the lava, I think I need to try something for that.

Eyebabe · #7 02-20-2011, 11:16 AM

I should also add that most of my plants are now S/H and given the lack of media issues that may also have helped eliminate/cut down fungus gnats.
Those little buggers love bark and eat the fungus that grows on it.
Dunks, Neem Oil once every 3 weeks, and mostly potting media that does not deteriorate.
I use the dunks/mosquito bits in the water I use to water the plants. You need to give a some time for the substance in the dunk to get into the water...
There was a really useful link about fungus gnats a while back and since I read it and made those changes I hardly ever see them.
I will do my best to find it