Gnat DefenseGet rid of those pesky fungus gnats with Gnat Defense! Gnat Defense is a highly effective gnat treatment that will treat fungus gnats and their larve. Pesticide Free! Sprinkle a thick layer of Gnat Defense ontop of DRY soil (not effective when product becomes wet) and let it do its magic! When the gnat larvae or adult gnats come in contact with it, it acts if they were crawling through crushed glass. *Use continuously for up to a month for best