This year I have an alarming number of fungus gnats that came out of the potting soil that I used to pot my amaryllis up. Please share your tips and what chemical you used. Thanks in advance.

The very best luck I have had with treating fungus gnats has been to use mosquito dunks in the water I water the plants with. The BT that kills mosquito larva also kills fungus gnat larva. And the great thing about it is it's totally safe to use around children and pets.

That sounds like a great tip, Tabby --if you haven't already done so, you should send it to Trish for the "tips" feature!

I have used the following methods:
1) watering with mosquito dunks
2) watering with hydrogen peroxide and water
3) putting up small containers with apple cider vinegar, it attracts the gnats a lot! Just remember to poke holes on the cover of the container.

Since the numbers have reduced a lot after watering with either no.1 or no. 2, I kept the containers with vinegar beside the plants, just in case there were adult stragglers left.

another good idea, Tarev -- use containers of cider vinegar to attract and drown fruit flies when my kitchen is full of tomatoes etc. from the garden.

I've found that the drier the soil the better, the gnats love wet soil to lay their eggs. I've also heard of putting a layer of sand over the potting soil to discourage the qnats from laying eggs. I used to water with a hydrogen peroxide mixture. About 3 years ago, I finally got tired of gnats flying all over the house, so I confined my bulbs, and other plants (brought in the house for the winter), to a heated glassed in "sunroom", which is closed off from the rest of the house. I put up fly paper strips on the glass windows: not very pretty, but effective for the 3-4 months that I use the room for plants. The gnats fly toward the outside light and get stuck. This keeps the gnats down to a reasonable level. When the flowers open, I bring the cut Amaryllis into the house to enjoy as cut flowers. I put a pinch of sugar into the vase, and I think they last just as long that way. Of course I am not looking for seed or trying to hybridize them.

bsharf said:I've found that the drier the soil the better, the gnats love wet soil to lay their eggs.

I think that explains why I haven't had much problem with them... my poor plants all have to learn to survive periods of drought !

Thanks everyone for all the tips you've shared. I appreciate it.

I make yellow jacket traps to keep down the number of yellow jackets bothering the bees.What have found is that the traps catch more houseflies,fungus gnats and moths than yellow jackets.
The traps are just a 1 inch hole cut about half way down a 2 liter soft drink bottle.The bait is a mixture of sugar water,cider vinegar and yeast.A litle crushed fruit pulp will make it even more attractive but keep the pieces very small as you will have to empty this thing often.Let me see if I can find a picture.
This one has been out only a couple of days.That dark layer is bugs.

JT, your trick will be useful for me outside once the hippis are out. Will try it and see if it could catch NBF. I have several amaryllis I lost due to them. Thanks so much.

I tried one of your tips and it worked! I used apple juice and orange juice separately. The apple juice (Cider vinegar after a few days?) trap caught more than OJ. Thanks again.