fungus gnats and seed starting

Linda Foulis
Wed, 09 Nov 2005 10:58:26 PST
Thank you all for your responses regarding the granite grit.

As for seed starting mixes, I'm always on the lookout for new and improved
methods.  I start seeds year round, when one only has an average of 112 days
frost free....  I garden indoors a lot.
I started off using a mix of 1-1-1, peat-vermiculite-perlite.  Over the
years I've reduced it to half and  half of peat and vermiculite.  Needless
to say, I'm still looking for the ideal mix.
With the perlite I found that it surfaces, and algae will grow on it easily.
Now that problem was solved by eliminating the perlite, however it creates
other problems.  My mix is less porous.  I switched to a larger grade of

I have gnat problems every year and I'm convinced that they comes in with
the peat.  I'm extremely careful about cleanliness.  This year is the worst
it has ever been.  I'm almost debating throwing out about a dozen trays of
seed due to this problem.

Insecticides of any sort have to be carefully researched in my house prior
to use.  I have allergies and we also have a parrot.  I liked vectobac, the
active ingredient being Bacillus thruringiensis israelensis, very effective
and environmentally friendly.  However I can not seem to find it anymore?
I'm currently trying a product called SM-90, made by Nutrilife, which
claims - 'Nutrilife's SM-90 is liquid magic for your plants. Made from plant
extracts such as corriander and canola oil, SM-90 can be used in the root
zone as a shield against pathogens, fungal gnat larvae, and root aphids and
as a foliar spray against spider mites. Safe enough to use regularly in
hydroponic reservoirs, SM-90 can act as a good method to promoting healthy
Is it working?  Some days I think I'm ahead of the game, other days I think
they are winning.  Sticky strips are everywhere.

Is there something that I can replace the peat with?  I love the idea of
using straight granite grit as I'm pretty sure that will eliminate my gnat
problems.  However once the seedling starts to grow I have to put it back
into a soil or soil-less mix?

Still at the drawing board! and becoming one with the fungus gnats!

Linda Foulis
Okotoks, AB

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