are there any pesticides that i can spray to mimimize the gnat problem. I...

Asked January 21, 2016, 11:05 PM EST

are there any pesticides that i can spray to mimimize the gnat problem. I have plants throughout the house and i am currently experiencing a severe problem with gnats.t

Baltimore County Maryland

1 Response

There is no pesticide that we recommend for fungus gnats. Please read over this short fact sheet about handling them: http://extension.umd.edu/hgic/fungus-gnats-houseplants

The biggest problem with houseplants is overwatering and fungus gnats tends to be a byproduct of our efforts to keep our houseplant hydrated. However, almost all houseplants are fine when the top inch of pot soil is allowed to dry out between waterings. (Many can tolerate much more neglect!) Another factor that causes overwatering is that in the plant's 'resting period' (usually this means the winter), they are not actively growing and so are not using nearly as much water as they do from spring to fall. Consequently, when we keep up our usual watering regimen, they are actually getting too much water because they can't use it all. Thus, fungus gnat breeding ground is created.

Usually fungal gnat larvae are in the top inch of soil, but in rare instances they get established in the bottom of the pot (It would have to be elevated enough so they can enter and exit.) In that instance, it may be necessary to replace the potting soil if the plant cannot tolerate letting the entire pot of soil dry completely.

ECN