I see these small black flies hanging around some plants I brought inside my home this past fall. They're really small and don't fly well but they're annoying. Worse yet I can't tell if they're living on the plants or in the house!! What can I safely use to kill them and do I have to spray the plant? I don't see them on the plant but they seem to be close by.
You most likely have fungus gnats. These are small black flies which like to live and breed in moist areas where mold or algae may grow. During the winter months, many people will unknowingly bring plants inside the home which have active fungus gnats living in the potted soil. When adults emerge, they'll be drawn to anything that smells like it's decomposing. Many times this will be around your nose or maybe on some fruits or vegetables out in the open. They can be quite disturbing indeed when you see them flying around at dinner time as they especially like ketchup, salad and other vegetables.
The good news is that fungus gnats are easy to control. In most cases drenching the soil of the infested plant will do the job since this is where the eggs are laid and the larvae live as they hatch from eggs. Adding 1-2 oz of VEGETABLES PLUS PERMETHRIN to a gallon of water and then watering the plant with this formulation will usually knock them right out. An organic option would be the same approach using our 3 IN 1 FIM featured on our Non Toxic Pest Control site. This product also works on fungus so it may be the better choice since it would help to reduce the food supply of this pest. This would indirectly prevent future populations by eliminating the food on which they need to live.
Fungus gnats can also live down drain lines and commonly find their way into dirty sinkerators or grinders. Garbage pails, litter boxes and compost piles in the home can all harbor fungus gnats so if you have any of these, be sure to inspect this area carefully. If you start finding them out in the open, keep a can of HOUSEPLANT SPRAY handy. This organic aerosol is easy to use and can safely be used inside all winter long. If you have any other questions or concerns, give us a call on our toll free 1-800-877-7290.
Here are direct links to the products mentioned above:
Vegetables Plus Permethrin: http://www.bugspray.com/item/vegetables_plus_permethrin.html