Janos, I use the wettable powder - 400WP. I've never had problems with fungus gnats but if I did I'm sure I'd use something with Imidacloprid or a related compound in it - something like Marathon. The only insects I spray against are aphids and I use the Imidacloprid for that. Best, John John T Lonsdale PhD 407 Edgewood Drive, Exton, Pennsylvania 19341, USA Home: 610 594 9232 Cell: 484 678 9856 Fax: 315 571 9232 Visit "Edgewood" - The Lonsdale Garden at http://www.edgewoodgardens.net/ USDA Zone 6b John, Did you used Banrot 400WP or 80G? I used copper oxychlorine weekly, i just dusted the surface with it and than watered the cuttings. I had terrible infestation of fungus gnats this year. I was able to kill them with chlorpyriphos. Do you have anything useful for gnats in the US other than Citation?