Short answer: Maybe.
Try it!
Vera is right- they could be immature bulb onions- just picked early. But there's more to it...
Long answer: Lots of 'name confusion' with onions: bulbing onion, green onion, scallion, bunching onion, spring onion-
The food industry hasn't helped define onions for us horticulturally.
Bulbing onions varieties, Allium cepa, are either day-length sensitive or somewhat day-length neutral to grow a big onion bulb. Onions then, can be somewhat manipulated based on variety selected. For example, growing 'long- daylength' onions in a 'short-daylength' area- means those onions would resist bulbing longer- giving a higher percentage of green onions, or immature bulbed onions (spring onions?) These technically are just immature bulbing onions that haven't fully bulbed yet. Furthermore, if your area doesn't have enough daylength, your onion may never bulb to your satisfaction in your garden.
It may, though, in a different area.
It might also be a hybrid, bred not to have a large bulb, as in the case of those varieties usually sold to gardeners as bunching onions, or pearl onions.
Discussing hybrids of Allium cepa bred with A. fistulosum, the non-bulb-forming Japanese bunching onion:
"This hybrid retains the characteristics that are desirable for green onions and resists bulb development even when grown in regions with long days"
That quote from this article, which will interest you.
https://www.wifss.ucdavis.edu/...
Fyi-
I've never been impressed with onion sets in my garden. I've been buying onion transplants by mail order each spring, so I can match the variety with my daylength for a great crop. The transplants also give me a jump on the season over seeds or sets. I can also choose 'sweet' or 'storage' (usually more pungent) varieties.
You'll notice my transplants could be chopped-up in my salad and called a 'green onion!'
Good luck on your experiment!
