Flies on houseplants

[Okz]

I recently repotted quite a few houseplants, as they were outgrowing their pots, with a bag of compost from B&Q.

A couple of weeks have passed and I have noticed the plants (and now the house) have become infested with flies. I think the bag of compost is the culprit as the other plants that weren’t repotted are fine. A quick google has identified these flies as fungus gnats.

I have a new born in the house so I’m worried about the infestation. They have got everywhere!

I'm reluctant to throw out all my plants - is there any other way of getting rid of the infestation? I am not sure repotting with new soil will help as the issue is right in the roots.

Please help - they are driving me insane!

I've just had this!
I'd reported and it was the compost.

The weather was warm.enough for me to stick the plant outside for a few days (I was away and didn't want to return to fly-hell) Then I sprayed with bug spray. 2 weeks on and all seems OK (no flies and plant not dead).

*not reported- repotted
The plant police didn't give a toss.

A familiar nightmare. Agree with exiling plants for a few days if possible and also putting gravel / pebbles on top the soil helps.

Have had these too - what worked for us - electric fly tennis racket to kill them en masse (sorry flies) and stop watering them so regularly as they like moist soil. Really like water them once thoroughly and then leave then as long as possible before doing it again!

Get sticky card strips and place in pot, the flies will soon be killed

I heard that watering from the bottom helps too.

Mosquito bits helped when we had this. They are small pallets that you put on the soil and basically leak into the soil and gnat eggs get destroyed so new ones don’t get born.

They are no danger to your newborn.

If you search “fungus gnats” on here, there have been several threads full of good advice.