Fungus gnats - argh

[Austriana]

I have over 40 houseplants and recently there have been what I think are fungus gnats flying around.

Has anyone use Baby Bio houseplant bug killer? I have never used pesticides on any plants, indoor or outdoor, before. I don't like to use chemicals, especially around my young kids.

That said, changing the soil of all of the plants would be tricky especially at this time of year ( I come home after dark).

Any advice would be appreciated-thanks!

Fungus gnats tend to spend time crawling up the outside of pots, so are relatively easy to squish by hand in that situation.

If you've got lots of them, it probably means that you have grubs metamorphosing into flies rather than a new invasion. My experience is that it's difficult to get rid of grubs in soil using insecticide, but I haven't tried the Baby Bio one.You could trust that pretty well all of the grubs have "hatched" by now, and concentrate on preventing a continuing infestation. Household fly killer gets rid of the flies quite effectively. Try a thick layer of grit on the top of each flower pot - they flies are after a humus-rich soil.

When you come to repot in spring, a soil based compost may be better than a peat-free one, and repeat the layer of grit over the top of the pot. Meanwhile, keep a close eye on all your plants - any which look as if they're lacking water may be lacking water because they have no functional roots because of the grubs, so you will need to deal with these, winter or not.

Many thanks, didn't realise that about the roots

I've just tried a nematode drench on mine for the same reason... Not sure yet how effective it will be, but the flies are driving me bonkers!