Anyway, this year I have a supermarket onion that fascinated me by sending out shoots. Just sitting on the counter it has 4 or 5 green fingers the width of my pinkie and about 5 inches long, and I want to plant it to see what happens. Is there anything that I need to do to try this out? I can plant it totally away from everything else I'm doing to avoid any contamination or disease risk or anything.

My only other allium experience is starting garlic from starter cloves all broken up and that's also this year and a few chives that somebody dug up for me. Do I do anything to the onion like splitting if I can plant it and expect anything?

Thanks!

I do this every spring with onions I have stored over the winter, so I have seed for the next planting.