Two winters ago I had flowering geraniums in my apt. all winter. Then the deadly fungas gnats arrived in a bag of potting soil. I got totally infested and wound up tossing my plants out. Now, how about the soil? I left it outside in sealed containers in our cold Canadian winter and want to know if that treatment will have killed off all traces of the critters, making the soil safe to use this spring.

I don't know if prolonged cold will do it. Some bugs can go into a sort of suspended animation over the winter, only to pop up again, as healthy as ever, as soon as the warm weather returns. :p Ticks can survive for two years w/o warmth and food!

Hi Joestuff,
Welcome to The Garden Helper's Forum!!!
We are very glad you found us!!!

I am by no means a house plant expert....

But I think Will Creed says something about
putting the potting soil into water, submerge it,
and let it sit for a while....
It drowns them, bugs and eggs???
I think???

I know Will's on vacation, hopefully he'll swing thru...

Weezie

P/S If no more replies come in as of late...
bring the post back up to the top.

FYI have you ever smelled baking soil? it stinks... i would just use beneficial nematodes for control of the larva if they appear and / or use yellow sticky cards to trap adults.

I don't know how to deal with a current infestation but I know that if you put a thin layer of sand over the top of your potting soil, it's supposed to keep the adults from laying more eggs.