hate fungus gnats and they’re def an obstacle in establishing a living soil grow. i’ve noticed they’re far worse in new soil than in no till containers that have been thriving for 3+ cycles. i always run into them when i try to add a nice mulch layer to newer containers. they just love that decomposing layer.
i think they favor bacterially dominated soil conditions so the more fungal life you can bring into your soil the less inviting it is for gnats. one trick i use is to sprinkle some fungal food as a top dress every couple weeks to keep that white fuzzy layer on the soil/mulch surface. way harder for the gnats to lay eggs or emerge thru that.
add some predator soil mites (hypoapsis miles iirc?) and some steinernema feltiae nematodes and that’s a decent defense. the soil mites tend to establish quickly but i usually reapply the ‘todes a few times a year. it’s a good idea to apply a portion of them via foliar and they’ll attack the adults as well.
but i’ve been seeing a lot of soil growers getting back to sterile media and salts. whatever works!
i think they favor bacterially dominated soil conditions so the more fungal life you can bring into your soil the less inviting it is for gnats. one trick i use is to sprinkle some fungal food as a top dress every couple weeks to keep that white fuzzy layer on the soil/mulch surface. way harder for the gnats to lay eggs or emerge thru that.
add some predator soil mites (hypoapsis miles iirc?) and some steinernema feltiae nematodes and that’s a decent defense. the soil mites tend to establish quickly but i usually reapply the ‘todes a few times a year. it’s a good idea to apply a portion of them via foliar and they’ll attack the adults as well.
but i’ve been seeing a lot of soil growers getting back to sterile media and salts. whatever works!