How do you guys control fungal gnats in your cacti pots...? Or am I the only one fighting them off ? I have attempted to use diluted hydrogen peroxide and sand on top to kill the larvae. Recently I switched to a broad spec. insecticide however none of them even put a dent in the population of fungal gnats. Finally tonight I used some gnatrol. I am still waiting to see any effects of this stuff but a few questions. Has anyone ever used gnatrol, and what were yall's results? Also what other ways have you guys found to stave off the fiends?
Thanks,
Will
Hi Will, I haven't had fungus gnat problems with any of my cacti & succulents but have had plenty of them in my carnivorous plant collection. As most of my carnivorous plants grow in a very wet peat based (organic) mix and the C&S don't perhaps this is the answer, maybe you need more mineral content in your compost or perhaps the compost is too wet (I guess this shouldn't be the case for your cacti?).
The gnats were a pain but I didn't bother with any insecticide on them and relied on my Pinguiculas to catch the adults when they emerged which works to some extent but might not be enough for a serious infestation (plus of course it only works if you already have a Pinguicula collection ). But as already mentioned I have never had this problem with my C&S plants, plenty of mealy bugs but no fungus gnats.
Soil is too wet. They like to lay there eggs in wet soil. I usually bottom water so the top stays fairly dry all the time. I also sprinkle Bayer's Advanced Rose and Flower Control systemic fertilizer and insecticide on the soil and water it in. It got rid on my mealy bugs on my cactus and jade plants.
Last edited by Ron43 on Tue Mar 31, 2015 4:10 am, edited 1 time in total.
Soil is probably too wet, but also too organic. You can get some control by using a less organic soil and stony top dressing, but once they are in there you've pretty much lost the battle. You might be able to get somewhere by soaking the pots in an insecticide. Peroxide is not an insecticide. In future, aim to sterilise the soil and then keep the gnats out, preferably with a more suitable soil.
g/day all gnats, i had the cocerns, so i asked around how to get rid of them, well a proven methord is to cut the top off off plastic coke bottle put the neck part up side down back in the bottle tip in apple cider vinger about 1/4 cup full, they,ll go in and can,t get out, all so at one of our garden store, sell a yellow sticky cardboard item, i cut in to 3 inch squares and stick it here there amongst my cacti,s plus up on the walls etc, roxettelilly australia
I'm not an expert by any means, but when I first got my aloe i had a terrible infestation going on. If you cant get rid of it by any of these means you can always replace the soil. I was fed up with it and knew I had the wrong soil mix anyway, so that's the route I went after three months. Take the plants outside and dump the soil, brush off as much from the roots as you can. I sterilized the plant roots (and also got the extra soil off) with a dilute hydrogen peroxide mix. I also used peroxide on the pots. I let it all dry for a bit and re-potted at my friends place since my apartment had a ton flying around, but you could put them in a different room. I left the plants there for a couple weeks till the gnats all died and have had none ever since. Probably overkill, but it did the trick for me.
? I have attempted to use diluted hydrogen peroxide and sand on top to kill the larvae. Recently I switched to a broad spec. insecticide however none of them even put a dent in the population of fungal gnats. Finally tonight I used some gnatrol. I am still waiting to see any effects of this stuff but a few questions. Has anyone ever used gnatrol, and what were yall's results? Also what other ways have you guys found to stave off the fiends?
). But as already mentioned I have never had this problem with my C&S plants, plenty of mealy bugs but no fungus gnats.