Hello I have this information printed out it really helps not just with the seeds that need cold but with over 200 species. You can print it out punch holes in the pages and wella. Its very helpful. Ok well God bless you and Happy Holidays.
Nalani
http://www.backyardgardener.com/tm.html

Are poppies, Papaver Somniferous seeds ,need to be sown in the late fall or by winter sowing or do they have to be sown in the spring when it's warm, I've read conflicting information. Thanks

Almost any hardy perennial will germinate well at fairly low temperatures. If not, they will germinate a few weeks later when it warms up.

Papaver somniferum are annuals and they really grow fast when it is warm. You can germinate them early to get the flowers a little earlier if you want. They don't need huge heat to germinate, room temperature is plenty, or outdoors in spring if that is more convenient. You should keep them cool if they germinate very early, or provide extra light to prevent stretching.