The 1/2 inch of sand on the top of the soil in the plant pots sounds like a simple solution.

Although I wouldn't buy the sand in the stores, since I know of a few spots to go dig it up in the ditch close to here. I probably would then 'bake' the sand to sterilize it before putting it in my plant pots.

Brenda

It sounds plausible... but it would only work for mature houseplants, I can't see 1/2 inch of sand doing any good to indoor seedlings. And I have never actually had fungus gnats in houseplants. Actually, I had none in my indoor sowing this year, not sure why.

It does sound plausible. But what I've tried this past winter is putting a few granules of a biological larvicide(Aqua Bac) into the plant water. Aparently the bacillus thuringiensis will also kill off the gnat larvae in the soil too. I had a really bad infestation in my indoor seeding this year, and the yellow sticky paper didn't cut it. Between those and the Aqua Bac in the water, it did really cut down a lot on the gnat population.

The best tip is not to over water, let your plants dry out a bit before watering again. Also clean up any debris that has fallen into the pots.

However, I can see that sand would work, the sharp particulars probably punctures their soft bodies.

I have a few plants, mostly cacti types with a layer of chicken grit on the surface, never seen a gnat in my house ;)

Sharon

Cool!

My kids tend to help me water the plants lately (with a bit too much watery-love) so I can "steal" sand from their sand box to fix the problem! LOL They've been learning that over-watering is not good but it sometimes does happen yet.

Ang