Thalia, I see no sense in working with very old seeds unless the variety is so rare that it's worth it to try and revive it.
In the early 90's Craig and I received lots of non-viable seed from varieties requested from the USDA and at that time we both tried all sorts of ways to wake up those seeds.
We tried the most common method recommended then, which was a presoak in K nitrate, we tried Microwave, we tried gibberellic acid alone and in combo with the Knitrate.
The nitrate ion is known to be involved in seed germination, thus its addition to soaked seeds.
Over the years I've settled on the method that you'll find posted in the thread in the General Discussion area by Brazos Valley on his seed germination of some of my seeds, and that's an o/n soak in water with a pinch of MG or Shultz for added nitrate ion or a few drops of fish or seaweed for the organic folks.
For some old seed I've had to wait several months for maybe one seed to germinate and Craig will remember well the one Magnus seedling I got after a two months wait. As far as I know, almost all Magnus seed out there now came from that one plant.
In terms of enhancement of germination, not waking up supposed dead seeds, I'll sow anything less than 5 yo as I would normally. From maybe 5 to 12 years old I might double sow, for seed over 12 years old I'll do the hydration routine described above.
And different varieties appear to have different seed viability traits, that is, heart shaped varieties seem to not last as long as others.
Two times I asked for feedback on seeds I distributed and the results were very interesting indeed.
Cutting to the chase, there was a huge variability amongst those folks who got the exact same samples. And that's b'c no two people sow seed in the same mix, use domes or not, bottom heat or not, sow at the same depth and all the other factors.
Most illuminating was the time I offered about 20 varieties that were fresh seed. Actually grown in the summer of 2004 and offered that Fall.
For any one of those the reports back showed rates form zero, yes zero, up to 90-100%.
I have hundreds upon hundreds of vials of old seed here at home dating back mainly to 1988 and forward. I won't bother with them unless someone is looking for a variety no longer listed at SSE or if someone contacts me and asks if I have it b/c they can't find it elsewhere after a documented search, and if I do it's up to them to try to wake it up, not me. LOL
So, I see no sense in fooling around with old seed unless the variety is no longer available, or, for some of us who have lots of old seed doing it just b'c we're curious.
Above I mentioned finding some seed that was sent to me by Don Podolia that I didn't know I had and yesterday I looked and there are two of them, one from 1991, the other from 1992 that I would like to see. Maybe this year, maybe not b'c I no longer can raise my own plants and I've received so many new ones this year, I mean not mentioned anywhere's, that those have first priority for the few plants that gardenmama raises for me.
Finally, if you do a search here at Tville, top of the page, and enter something like germinate old seed you'll see that others have posted several other methods, like using wet towels, soaking in cold tea, etc.
But there's a difference between trying to enhance germination as opposed to working with almosty non-viable seeds . For instance, that USDA seed that I mentioned bove had several varieties where maybe 1/50-100 seeds ever germinated.
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Carolyn
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