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Re: Sterile seed mix

Tim & Christa wrote:
> 
> I keep reading about sterile seed starting mix.  Is it safe to assume
> that store bought seed starting mix is sterile?  My bag doesn't say
> sterile, but it is a seed starting mixture.

Hi Tim and Christa!  

Seed starting mixtures, or Propagating Media (ooh..fancy!) should
ideally be pasturized as opposed to sterilized.  

The pasturization process uses lower temperatures and doesn't flat out
blast everything in the soil to kingdom come with super hot steam or
dangerous chemicals (They "scent" one soil sterilizer, Methyl bromide,
with TEAR GAS for example, because it is otherwise undetectable, but so
deadly it can drop you in your tracks with just a whiff).   

Those Rhizospheric organisms, like benificial nematodes and symbiotic
nitrogen- fixing bacteria, are good guys, and needn't be eliminated;
however, to answer your question, most retail planting mixes are steam
sterilized and are an ok first step in propagation. Much better than
soil from the garden.

Further aseptic techniques will also help:  Keep your propagation area
clean.  Treat tools, surfaces and yourself like they were in a human
doctor's office.  Wash up, don't cross contaminate, dip tools in and
wipe surfaces with a 1:10 clorox solution.  Don't reuse soil mixes and
thoroughly clean pots with the bleach before using them again.

The propagation environment is good for seeds, cuttings and,
unfortunately, fungi and mold and other nasty stuff. Keeping things
clean will go a long way to avoiding this.

Good luck!  Hey, what are you growing this year?

Glen Seibert
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