How To Get Rid Of Gnats In Plants Apple Cider Vinegar. That's because while gnats are small and light enough to land on water (or apple cider vinegar), dish soap breaks the surface tension of the water, meaning when they land on the surface to get a drink, they'll instead fall into the liquid and drown. Use the transparent tape to seal the cup.
The answer is to quarantine new plants or those that have been outdoors for extended periods. The smell of the fruit will attract the flying gnats towards the trap. Ensure that they are protruding out of the liquid in the cup.
