RE: HYB: Seeds Germinating

I have NEVER had one seed germinate earlier than the twelve weeks for me
I've had some come up after only 8 weeks, most after 12. The only SDB cross I've burrito'd started to sprout in less than 8 weeks.
I should have clarified - the seeds I'm concerned about being killed by sudden freezes are the ones in pots outdoors - some were planted dry this fall (mid October), most are hold overs from last year. We had more cold weather earlier than usual, so these outdoor seeds will have their 3 months of chilling long before temperatures can be counted on to stay "warm". Night temperatures were often below 40oF starting in late September, so by January, they will have been chilled for about 3 months. There were some seedlings coming up back in November in the pots held over from last year. Fortunately, that round of germination seemed to be done before the severe cold hit (teens F).
Prior experience says the pre-chilled seeds will be fine after a month at "warm" (<60oF) temperatures germinates all those that are ready and I pot them up.
I guess I will plan on bringing them all in to the unheated sunporch in Jan for a month if it turns really cold. Drat. Main reason I planted half of seeds outdoors this year was so I wouldn't have to be messing with seedlings from everything all winter, assuming we'd have another mild winter.
Under similar conditions, I got approximately 70% germination last year. If freezing hurts the seed in the freezer, why doesn't it hurt them outdoors? What is the difference? Betty
The difference is whether or not they have started to germinate when they are frozen, how cold it gets, and how long they stay frozen. If your crosses need at least 3 months of chilling <before> they germinate, they won't be hurt by freezing within that three month period. But a seed that has <started> to sprout (even if it's underground) will be just as sensitive to getting frozen solid as a 4 leaf seedling above ground. 

I think....
I don't know how temperatures <below> freezing affect vernalization rate. If one month of the three is below freezing, does that matter? Or do they need a total of three months below 40oF and above freezing? 

--
Linda Mann east Tennessee USA zone 7/8
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