Hey DGC!
A few weeks ago I started having a problem with fungus gnats in my grow room. Really weird because I’ve never had a problem before with gnats during the winter!
Chances are they came into the house via nectarines or another fruit.
Anyway, I tried almost everything to get rid of them to no avail, until I came across a video about neem cake.
Neem cake is the de-oiled residue that can be used after the neem seeds have been crushed for their oil.
These cakes or pellets contain NPK and have nematicidal properties.
When used as a soil drench they disrupt the feeding and breeding cycle of crop eating pests.
It controls soil based pathogens as well as nematodes. It also inhibits nitrification of the soil plus enhances the efficiency of nitrogen providing fertilizer.
These are just some of the benefits of neem cake.
I decided to try a soil drench daily over a one week period.
It’s been 3 weeks since I’ve used this product and the gnats are gone!
Here are the directions for use:
Add 3 tbsps of neem pellets to 1 gallon of water. Shake well and let sit for a minimum of 3 hours or longer. Shake the bottle from time to time to allow the pellets to disintegrate. The water should end up being a muddy brown colour. Ph the water and then drench your soil.
I fed my plants with their regular feed in the morning and would use the neem cake water later in the evening.
I did this daily for 1 week.
Any remaining liquid should be discarded because the longer it sits the worse it smells. Pour the leftover water down any drains close to your grow because gnats can live there too!
It was an inexpensive fix and I hope this can help others who are battling this pesky pest!
Thanks for all you do to help make us better growers!
I’ve tried BT, diatomaceous earth, and neem spray. I’m gonna try the neem cake next. If that don’t work, I’ll try some beneficial insects when it gets warmer. I keep ordering BAS soils hoping to get some free beneficials, but so far no luck. Funny. Rasta Jeff just went on a 5 minute rant about how he hates neem and it’s not allowed in commercial grows in Colorado. He recommends nuking the top layer of soil with a couple of Evergreen pyrethrin drenches and then re-inoculating the soil with microbes, aka Recharge. Pyrethrin comes from chrysanthemums. My worm bin is the primary source of my gnats. I feed them primarily freshly used coffee grounds so it’s always moist. That’s where the neem cake is going first.
I used to put name meal seed in my soil mix for nitrogen, and also the help of an insect deterrent. I think iI used to put name meal seed in my soil mix for nitrogen, and also the help of an insect deterrent. I think it might’ve worked. I didn’t have much of an issue back then. How much of t I didn’t have much of an issue back then. How much of the nitrogen do we have to include the nitrogen As a nutrient, when it is in cake form? I had loose meal.
Steinernema feltiae! that and a mean fan game.