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  • Serious Fungus Gnat Infestation

    Created by john on

    I have several mid size planters filled with young plants and I saw the fungus gnats as a minor problem until they were literally pouring over the soil like a living carpet. My recent transplants all seem to be dying off and now they seem to be impossible to remove. Is there anything I can do to get rid of these gnats for good without using harsh chemicals? This is a serious infestation and I have a pregnant wife to be concerned for? Do I need to dump everything (far away) and start over? Please help!

  • Author
  • #237291

    Eric Vinje

    Hi John –

    Yes, it is possible to get rid of fungus gnats without using toxic chemicals. Here’s what we recommend (https://www.planetnatural.com/pest-problem-solver/houseplant-pests/fungus-gnat-control/):

    • Inspect plants thoroughly prior to purchase for signs of insect pests. Turn up soil carefully near the base of the plant and look for the glossy, clear larvae. Reject any plant sending up flying gnats.
    • Fungus gnats do best in damp soils; be careful not to overwater, especially during winter months when plants use less. When potting, avoid water holding, organic material such as peat moss that may encourage egg laying.
    • If pests are present, allow the soil to dry to a depth of one to two inches between waterings. This not only kills larvae and inhibits the development of eggs, it also makes the soil less attractive to egg-laying females. Apply Gnat Nix as a top dressing to significantly reduce pest populations.
    • Use Yellow Sticky Traps placed horizontally at the soil surface to capture large numbers of egg laying adults. The gnats are attracted to yellow and are easily removed on the trap before they can lay more eggs.
    Mosquito Bits and Microbe-Lift® BMC contain Bacillus thuringiensis var. israelensis, a highly selective biological pesticide that kills damaging larvae, yet is SAFE for fish, wildlife, humans and non-target species. Contains NO harmful residues.
    • Top dress houseplants with Beneficial Nematodes to destroy the larvae stage. Nematodes are microscopic round worms that penetrate fungus gnat larvae, as well as harmful lawn and garden grubs , fleas, and other soil-borne pests (they do not harm earthworms), then release a bacterium that consumes the pest from the inside out. The long-lasting nematodes are safe for use around pets, plants, and your family.
    Flying Insect Killer, a combination of peppermint, cinnamon and sesame oils, is a non-toxic spray that will get rid of gnats and other insects that gather around windows.

    Hope it helps!

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