Help Fungus Gnats!

[Kateo]

Hello Orchid Experts,

I have a fungus gnat infestation. It is spread throughout my orchid collection and companion houseplants. I have been reading that mosquito bits tea can be very effective as a soil drench on plants. Is this ok to water orchids with? Or will it harm the roots? I am open to other treatment options, as well. Currently, I am using yellow sticky traps but I haven't seen a reduction in the fungus gnat population.

Your expertise is most welcome :-)

Thank you,
Katie

[dbarron]

I've had fungus gnats a couple of times in my normal potting soils. It means you're keeping them too wet as a general rule.
Never seen it (maybe I'm lucky) in orchid with a bark mix or even in spaghnum.

[Ray]

Mosquito Bits/Dunks are inert substrates carrying Bacillus thuringiensis bacteria. They infect the eggs and larvae, killing them.

It is perfectly safe for orchids, but you need to add the stuff to (preferably) chlorine-free water and let it soak for a few days so the dormant bacteria become active and start reproducing, then water. You'll want to keep using it for a couple of weeks, as it does nothing to the adults, which can lay more eggs.

I have recently found Southern Ag's Thuricide BT, which contains the same bacteria in an active form, as well as their secretions, making it instantly toxic to the critters.

[Subrosa]

When life give you fungus gnats, grow Pinguicula:

[DeaC]

Love those Pings. I've only had 2 for 6 months but they work and fun to observe how they grow. Considering Drosera as well but reading about both needs to be done first. Carnivorous Plants For Sale - Buy Sundews, Butterworts, Flytraps and more! was my source.

[Maree]

I agree with Ray. I had a bad case of gnats and I dissolved a piece of a dunk in a bottle of water and followed up my usual watering with a few splashes of the dunk water. It took several weeks but it was successful and EASY.

[Subrosa]

Originally Posted by DeaC

Love those Pings. I've only had 2 for 6 months but they work and fun to observe how they grow. Considering Drosera as well but reading about both needs to be done first. Carnivorous Plants For Sale - Buy Sundews, Butterworts, Flytraps and more! was my source.

Pinguicula are better suited to windowsill culture than most Drosera. Drosera generally prefer stronger lighting and do best either outside in full sun or under lights.

[realoldbeachbum]

Just recently Mosquito Bits killed swarms of gnats in my collection. I did two drenches one week apart, then sprinkled a few bits on surface of the media. No more fungus gnats!

[DeaC]

Originally Posted by Subrosa

Pinguicula are better suited to windowsill culture than most Drosera. Drosera generally prefer stronger lighting and do best either outside in full sun or under lights.

TY. My 2 pings are under lights throwing out flowers and still seem to be in the succulent stage or rossette stage. Still reading up on them and terminology. So Drosera will be next on the list.

[alecStewart1]

Originally Posted by Subrosa

When life give you fungus gnats, grow Pinguicula:

The bonus with Pings is that they have nice flowers like orchids! Plus, you can usually get pings for under ~$30 (USD), unless it's a special cultivar and/or hybrid.

A lot will actually breakdown pollen from other plants or even smaller plants that get stuck on their leaves, as well as bugs.