Re-sprouting onions...

[Peteyd]

We've just got back off of holiday and when checking out the garden it would appear I must have forgotten about my onions. (namely I didn't harvest them)

They have started to sprout again. Is it worth leaving them in the ground for next year or should the just head for the heap?

They were Overwinter senshyu onions planted last year.

[Martin H]

I would dig them up now and chop and freeze the good bits of the bulbs. If you leave them they will flower in the spring.

[Jay-ell]

They'll send up flower shoots in the spring so you can

1. Harvest them now and freeze whatever can be salvaged
2. Let them grow a number of leaves and harvest them as green onions
3. Let them throw up up the flower stalks (scapes) and harvest them to cook along with the greens.
4. Let them grow scapes, harvest them and then let the onions continue to grow on - a lot may be inedible, some may form new bulbs and some may split and form multiple bulbs. (this option is really for the curious and experimental mind, rather than a chance of a reasonable harvest)

[Snadger]

I would just bin em and utilise the ground for summat else.

[Snoop Puss]

Leave them and harvest them from December onwards and use as scallions and leeks. Or barbecue as calçots. Anyone asks, you were always intending to grow them as calçots, which are starting to turn up in restaurants in London (and possibly elsewhere).

https://en.wikipedia.org/wiki/Cal%C3%A7ot

The wikipedia link isn't terribly informative, but there's loads of other stuff on the Web.

Here's a better link with more pictures.
https://devourbarcelonafoodtours.com/calcots/

The onion bulb itself will rot as the shoots grow. If any of the onion bulb is left at the base of your shoots, just clean it off. It doesn't look very nice, but if you remove it and then cook the shoots, it'll be perfectly OK.

[Thelma Sanders]

I would dig them up now and chop and freeze the good bits of the bulbs.

That's what I did with mine, I double bagged them to stop the smell escaping

[Penellype]

I grow enough onions to last the year and always find a few start to sprout in spring. When they do I salvage the edible bits, chop and freeze. They are fine for cooking straight from the freezer.

[Mark_Riga]

I would harvest them as you want to use them adding the green tops as well as the main part of the bulb to whatever you are cooking. Or use the green stems with cheese on a sandwich and cook the rest or .... basically, I would eat them.

[Peteyd]

Great, thanks for the advice. I'm all for trying new things. I'll harvest them and see what is salvageable.