How to Kill Bugs and Gnats on Your Houseplants

Houseplants are no place for fungus gnats and other bugs.

Even though your plants are indoors, they are still susceptible to bugs. Fungus gnats and other critters will occupy a houseplant and sometimes cause it harm -- they can chew on the leaves and stems and lay eggs in the soil or on the plant. They will usually fly around your house and annoy you, too. Since the bugs are often destructive, take measures to remove them, so that the plants won't die. Different techniques are available to get rid of those bugs and reclaim your plant.

Things You'll Need

• Yellow sticky traps
• Cotton ball
• Isopropyl alcohol
• Tweezers
• Container
• Trash bag

Instructions

1. Place a yellow sticky trap on the plant's soil. The bright color often attracts gnats and other bugs to the trap, where they are then stuck to the adhesive. Remove the covered trap and replace it until no more are collected.

2. Dip a cotton ball in isopropyl alcohol and wipe it on the plant's leaves and any bugs you see. The strong liquid is typically effective in eliminating some pests, including the mealy bug. However, the alcohol can burn some plant's leaves; therefore, test the alcohol out on a small patch of a leaf before applying it to the entire plant.

3. Pick the bugs off the plants using a pair of tweezers. Although you likely won't grab the fungus gnats, you can usually grab other critters, such as aphids, off of the plant with this method. Place the collected bugs into a lidded container. Pour boiling water over the bugs to get rid of them and then toss them in the garbage.

4. Allow the soil to dry out in between waterings, if fungus gnats are the problem. The upper inch of soil is where fungus gnats are typically found. Reducing the moisture in the soil will often get rid of the fungus the gnats feed on.

5. Prune your plant if only a few leaves are affected by the infestation. Throw the leaves away in a thick plastic bag and place it in an outdoor container.

6. Throw the plant away if it has died from the infestation or you can't get the bugs under control. Keeping the plant only exposes other plants to the bugs and increases their chances of becoming infested as well.

Tips & Warnings

• Keep new houseplants away from others for at least 2 weeks before you introduce them, to prevent accidentally spreading bugs.

• Always used sterilized soil when potting plants.

• Sticky traps are often available at hardware stores and garden centers.

References

• Colorado State University Extension; Managing Houseplant Pests; W.S. Cranshaw; 2006
• New Mexico State University; Fungus Gnats on Houseplants in Summer; June 2000
• University of Minnesota Extension; Houseplant Insect Control; Jeffrey Hahn, Deborah Brown and Mark Ascerno; 2005