Fungus gnats in houseplants

[LesserKnownKardashian]

Not really a gardening question, but I thought you knowledgeable people might be able to help.
I have an infestation of fungus gnats. So far, I've tried:
• letting the soil dry out
• capping the soil with gravel
• carnivorous plants (they've trapped loads but more keep coming)
• putting all the plants in one room and using fly spray (most effective, but the larval stage is around 2 weeks, so I'd need to keep doing this and I prefer not to use too much poison in the house)
• yellow sticky traps (useless so far)

Any better suggestions? I really don't want to get rid of all my plants. ☹️

I put a mixture of water, vinegar and a spot of washing up liquid in a ramekin among my plants. It did attract (and drown) loads. I've now got a spider living in the corner of the window, that seems to have helped a lot.

I think I'm happy with control rather than eradication.

Nemotodes. Add into water and just water the plants as normal. About £7 from amazon and other places :) Sometimes listed as for scariad

Mosquito bits. Can get them from Amazon. Follow the instructions, soak them, let them dry out for a couple of weeks then do it again. Repeat until it's under control. I have this problem and have tried all the things and this is the only effective thing I've come across.

Another vote for nematodes. The official name is "sciarid fly" I think.

You need to remove the first inch of soil and replace with fresh. This will get rid of all the eggs too.

Cap with gravel or sand. Doesn't need to be fancy.
Water from the bottom, and don't let the top ever get damp,so they don't want to lay their eggs there kn rhe 1st place.

And apparently cinnamon sprinked on helps deter, or get rid of them. Can't remember which. I've recently sprinked it on my plants and haven't seen any since, but that is not really much of a recommendation really!

I asked this a couple of weeks ago. Was advised to get nematodes. Flies are all gone now! Nemasyd scariad fly killer from Amazon. Cost 6.40 Inc. delivery

Sorry nemasys

Nematodes sorted them out for me too. I had to do it's twice, but there was enough in the packet.

Thanks all.
Nematodes are on order; I'll update with the results.

How did you get on, @LesserKnownKardashian? Same issue here now.

There's far fewer of the little buggers, but still the occasional one. I might do it again in January if there are still some then.

I've just done a repeat treatment on mine. Always had loads of house plants. Never had this before

@LesserKnownKardashian any joy? I'm infested!

I had to get rid of the affected plant. Luckily it was only one. I found the yellow sticky things good.

Yes, I had just about got rid of them when I brought my hyacinths in from the shed. Now I need to do all the houseplants again. 🙁
And throw the bag of compost out!

Right. I have some nemasys and I'm totally flummoxed by the instructions. I only have 6-8 small house plants to treat. This is telling me about 4.5 litres of water and sticks solutions and soil drenches....

Anyone care to tell me how they did theirs?

I would just make it up in a couple of litres of water, stick the plants in a bucket then pour the stuff in. It will be more concentrated, but I don't suppose that will matter. Leave the plants to stand for an hour or so, then tip the remaining nematode solution in the garden when you're finished.