Hi Galtonia, I have never purposely sown Phytolacca americana, aka Pokeweed, because the birds sow it very well for me! I have literally hundreds of them in the back yard, and am constantly pulling them out.

My guess is this seed requires between 1-3 months of vernalization or "cold stratification". It would probably be perfect for winter-sowing. I am not sure though what you mean by Pokeweed roots needing vernalizing. The roots are very thick and tuberous and quite hardy in my zone 5.

Where are you planning to plant your seedlings?

What are you planning to do with your poke?

I loved poke greens as a kid in Oklahoma, but now find it as one of my most hated weeds. Still have an occasional meal of it but mostly tear it and my hair out as it self-seeds everywhere. I would think just throwing them out on fresh soil lightly covered and wait till Spring to transplant to desired (Desired? LOL) location.