Fungus gnats

Susan B
Fri, 25 Mar 2011 08:27:05 PDT
I tried the sand method and it didn't work for me.  Also tried the cut potato 
method (lay a cut potato on the soil, the larva go to the potato), and that 
didn't work, either.

From: "" <>
Sent: Fri, March 25, 2011 11:16:07 AM
Subject: Re: [pbs] Fungus gnats

I read that pouring a layer of sand on

top of the soil in a pot would eliminate fungus gnats,

reportedly because the sand cut up gnats or their larva, 

Nice thought, and widely believed to be true.  But not so.

Instead, use  Bacillus thuringiensis israelensis (Bti) as was suggested very 
early on in this thread.  Use the Bti (dissolved in your irrigation water) for 
at least 3 weeks to break the gnat's life cycle.

Jean in Portland, OR


More information about the pbs mailing list