Best solution to kill gnats?

I don’t want to spray my plants with anything if I don’t need to. I’m trying a small bug zapper turned on over night hopefully it will attract some of the few gnats I see. Lately I’ve been noticing a few tiny gnats the type fruit attracts. Also I’ve tried drying out the soil but the Gnats still hang out.

Even if you let the soil dry pretty thoroughly between watering, you may still have a few gnats hanging around. Your best bet is sprinkling diatomaceous earth on the top of the soil and yellow sticky traps.

Where can you find that powder?

Check you local hardware or garden/nursery supply outlet, or online, it is readily available anywhere.