Your fragile, growing vegetable seedlings are susceptible to a number of potential threats, from rabbits and squirrels to gnats. The larvae of fungus gnats consume a plant's roots, making it difficult for the delicate seedling to grow into a healthy plant. It's possible to control a fungus gnat infestation on your outdoor seedlings without using harmful chemicals.
Clear away any compost, decomposing leaves, mulch or other organic materials from areas where fungus gnats are an issue. Fungus gnats tend to breed in the damp leaves or mulch.
Mix predatory nematodes, such as Steinernema feltiae, with water then either drench the soil around the vegetable seedlings with the mixture or apply it with a sprayer. Predatory nematodes, which you can buy from garden centers, feed on the fungus gnats, keeping their numbers down.
Scatter yellow sticky traps around your garden. Choose a trap that is either flat, which you place on the ground near the affected seedlings, or hang a traditional fly trap from a stake or fence post. The gnats are attracted to the yellow color and cannot remove themselves from the trap. Change the traps weekly, or more often, as needed.
Combine 1 cup white vinegar and 1 teaspoon liquid dish soap in a bowl. Set the bowl outside where you see heavy gnat activity. The gnats are attracted to the vinegar's odor, and become weighed down once they enter the bowl. Change the bowl daily. If the infestation is dense or spread over a large area, set out several bowls.
Things You Will Need
- Hose sprayer
- Yellow sticky traps
- White vinegar
- Liquid dish soap
- Install sodium light bulbs outside to cut down on the number of fungus gnats infesting your garden or backyard at night.
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