Fungus Gnat Elimination: Alcohol Drench and Cultural Fixes

Persistent fungus gnats despite vinegar traps. Owner has pyrethrin insecticide.

Alcohol Soil Drench

Water with 1:1 water:rubbing alcohol – kills larvae in soil.

Dry out between waterings – wet soil = root rot = gnat food.
Empty drain trays 1 hour after watering – no standing water.
Check for bad soil – recent repotting with contaminated mix is common cause.

Kills adults only. Larvae in soil keep producing new adults. Alcohol drench + drying out targets the source.

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