Fungus gnat Larvae in flower. HELP!

Hey guys I just found some Fungus gnat larvae crawling on the leaves of my plant. The plants are in week 3 of flower. I’m letting the soil dry out and watching the soil with a moisture meter but I’m asking for advise on a quick killer that is organic and safe for my flowering beauties. I’m thinking about spraying BT on the soil but before I do anything I’m asking the wise men of the forum to help me out. Any suggestions?


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Do you have a pic of the critter? Usually fungal gnats larvae stay in the soil and eat roots until they are adults. Thrips appear as larvae on the foliage because that’s what they eat. Capt Jack’s dead bug is my go to in flowering. Don’t use neem oil. @Myfriendis410 recommends a peroxide/water mix a lot but I don’t know his mixing ratio.
Edit. You posted the pics while I was typing that :+1: looks like thrips to me, either way, Capt Jack’s dead bug will work


50/50 peroxide and water. If that doesn’t do it; straight 3%. If that doesn’t do it; 50/50 peroxide and water.


For fungus gnats use BTi. It’s the active component in mosquito bits, and is available in powder form from eBay (I prefer the powder).

I’m not sure that’s a fungus gnat. Their larva are typically found in the soil. That’s where they do the damage.

@RandomlyRan is probably right. It looks more like a thrip. Are you seeing small silvery patches or smears on the leaves? You can try the peroxide method, but keep it out of the soil. My go to is Monterrey insect Spinosad. It’s omri rated.

Captain Jacks dead bug also has spinosad, but it’s not OMRI rated.


Good organic alternative. Nice. I will look for that.

It looks like a spiders nest

I used Captain Jack’s once and it wiped them out

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