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Wednesday - July 22, 2009

From: Abilene, TX
Region: Southwest
Topic: Non-Natives, Pests
Title: Why are there gnats in my houseplants?
Answered by: Joe Marcus


I have flying brown gnats in my house plants. Can you tell me why?


The focus of research and the extent of expertise of the Lady Bird Johnson Wildflower Center are limited to North American native plant species.  Since few if any native plants are grown indoors, your plants and your question are outside of our purview.

However, we may be able to point you in the right direction for getting a satisfactory answer to your question.  Gnats around houseplants are usually one of a group of insects in the fly family called Fungus Gnats.  Here is an excellent article from South Dakota State University discussing Fungus Gnats, their life history and control.  The article was written for orchid growers, but the same principles apply to all houseplants.


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