Mammoth Improved onion: overwinter outdoors for seed?

[bower]

True, true, I haven't a clue!!!!!

I have some Mammoth Improved in the field that were planted late and didn't bulb. I wondered if I could overwinter them outdoors with a little mulch? Or lots. And save seeds next season.

I guess I could also bring them in and overwinter in the greenhouse, but it's a PIA when the alliums start to flower so early that there aren't any bees outside yet....
Anyone know about the frost tenderness of the dear Mammoth?

I really like these onions, the seedlings were so sturdy it was a pleasure to grow.

[NewWestGardener]

Bower, what you have there might be from the seeds I sent in. I think I still have extra seeds if want more. If have a greenhouse and time , you may get started in November for bigger bulbs next year.

I'll be sending in their cousins (seeds)for our trade this year :The mammoth leeks. They are great too.

[bower]

NewWest, they did come from Nicky's swap, and what a lovely onion. Thank you for sharing it! And the leeks sound awesome as well.

Since I didn't know what to do I decided to split them up - ten sturdy ones I transplanted to a sheltered spot where I'm going to mulch them heavily with kelp after they settle in. We'll see if they survive. If not, a lesson learned.

And I have a dozen more that I'm going to make a place for in the greenhouse.
Your seeds were awesome btw, every one sprouted.