Hi Ginny, what a nice surprise to see this! You should have stood beside them for the photo
. The Shadong people would have enjoyed seeing their humble onions made it big in the United States!
I'm glad yours worked out so well as you really took good care of them.
You could also experiment a little by leaving a couple of them in the ground, bury them with more soil, to see if they come back again next spring. I think they will, even if your ground freezes solid in the winter. You will likely get big tender sprouts in spring, leave a couple in ground for seed collection later.
They are referred in China as 山东 大葱 "Shandong Giant Green Onion" or "Shandong Da Cong", even if they are grown elsewhere. So the region becomes the generic name, however, I don't think there is a name to this specific variety as the seeds were bought at the local market, loose without labels, but safe to say they are local heirloom.
I just planted some this morning. They will overwinter, and ready for next year. My crop died of thirst this year as I did not water them at all and this summer was the hottest and driest. I still have a few seeds left from last year, which I will package up and offer up for trades later this year, if they germinate well. I will know for sure in a week if seedlings emerge. Gulp....Just realized that my dog dug a hole in the bed I just planted... what can I say!