How do you get rid of gnats flying around your house plants?
Try placing a layer of sand on top of the soil around the base
of the plant. The gnats are attracted to over-watered soil and
their larvae are in the soil. Sand will keep the flies from laying
eggs. It has also been suggested to spray the plant/soil with soapy
mixture. Good luck.
I would also try the ole plastic over the cup o' vinegar trick.
Place a cup or small bowl of vinegar with a dash(squirt) of dish
soap, cover with plastic wrap, cut or poke small holes in the
plastic wrap, viola'...Nat catcher!