Community

Posted 1w ago by @hailey.jaynes

Fungus gnat larvae
I recently watered my peace lily from the top as i thought I had successfully evicted all fungus gnats - I haven’t seen an adult fly in weeks! But when I did so all of these tiny white worms came flowing out with the drainage. Are these more larvae? I don’t understand how they are getting into the pot after I have been exclusively bottom watering (prior to this) and have allowed the top soil to dry entirely. The topsoil has no evidence of larvae that I can find, and is covered in cinnamon. Any thoughts on how they are still getting in? How should I get rid of them? There seems to be at least 100 or more larvae, should I be worried about root damage? HELP!
I had a huge infestation this past fall and that is what the larvae looked like in my pots. I religiously watered with mosquito bits tea and also used a neem mixture that I sprayed on the soil surface. It was about two months before I had it under control. I also stopped using organic fertilizer for a while. So, I can't say what specifically was the magic remedy but I did finally get rid of them. The advice of bottom watering only did not work because the flies would just lay eggs in the drainage holes. And boy did I have drainage holes because I have my over-wintered plants in air-pots. They followed the moisture in my case. I have the neem recipe written somewhere in my notes. I'll look it up if you want to know it but I can't guarantee it did anything as I religiously did several things simultaneously. There are many sources that swear quality cold-pressed neem oil will disrupt the development of larvae into adults. I can't speak about root damage but if you're worried and your plant is healthy you could repot it and check the roots to see if they are rotting or being used as food. I think I was overwatering at least a couple of my many plants so it's possible the flies were attracted to rotting roots. Really you'd have to detect a bad smell or physically look at the roots to know if they are damaged (or rotting).
if your peace lily is indoors and you have no pets that eat your plants/dig their soil, some systemic insecticide in the soil would be helpful :) heard mosquito bits are also good for this but i mainly stick to the systemics. i would also put some yellow sticky traps in the meantime to get rid of the adults!
@strawberrymoon yes luckily i was able to get rid of the adults with the sticky traps a few weeks ago but it seems more might be on the way! In Canada mosquito bits are banned but I will see if I can find a systemic, thanks!
@LordRubbervine Thank you for your help!
@strawberrymoon good call. I was dealing with fungus gnats on edible plants so I didn't consider systematic pesticides. That would likely be an easier solution if the situation allows.
I completely forgot to mention that I used steinernema feltiae nematodes to knock the fungus gnat numbers down quickly. I ordered them from Amazon and applied them to each plant pot. They made an extremely noticeable impact within a handful of days. I had a really bad infestation in my house so I ended up spending a (very) small fortune but at least I know how to eradicate the little [censored]s should they return.
Thank you both so much for your help!

See more content like this

Growing healthy plants can be intimidating, but you’re not in it alone. Get inspired from other Greg users!
Discover the Community