I have gnats in my house plants–what can I do about them? And how do I properly repot my plants?
The Gardener’s Answer
Hello, Desiree in Ohio: Fungus gnats are more of a nuisance than anything. They will not harm humans or animals, but the larval stage of these gnats live in the soil of our plants and can damage the roots, so control is necessary to prevent plant stress. Good sanitation and drainage will help keep the numbers down. They like to lay their eggs in damp soil, so make sure the plants are not being overwatered and there is no standing water in the saucer. Sticky fly traps are a great way to eliminate these pests. You should be able to find these at your local garden center. They are exactly what they sound like. They are bright yellow and sticky and you can either lay them in the soil or just place them around the house and the gnats will find them. The flying adults are attracted to the color, and once they come into contact with the trap they will not be able to free themselves. This will prevent them from reproducing and stop the cycle. There may be many generations in one year but their life cycle is approximately one month long. Check and replace the traps once they are covered in these insects. As for the plants that you repotted, the general rule is to choose a container that is no larger than 2 inches than the containers they are currently growing in. Planting them in containers that are too large makes them more susceptible to root rot because of excess soil. All plants have different growing requirements in terms of moisture levels and sunlight. I cannot give you specifics not knowing what you are growing, but hopefully the plants still have the grower’s tags in them. Make sure all of your containers have sufficient drain holes. Most plants except for succulents require water every seven to 10 days during the growing season and they can be fertilized once a month. If you find the names of your plants I can give you more detailed information.