They might bolt anyway. They are normally planted in midwinter, live a year, and then bolt the following spring.

Having been planted in the fall, they may feel they have now had their requisite one full winter and it's time. They don't all get to an inch. They can bolt at pencil size.

Leeks also have pretty big, dense root systems. I would not put them closer than 8 inches, and are you really gonna transplant them for that?

What I think you should do, if you want the space, is eat them :). If they are too many to eat right now, you can fry them up and freeze them. They will keep a year in the freezer if you squeeze all the air out of the package.

Thanks, Nila! I looked up exactly when I planted them as fairly fat seedlings: October 28. Autumn, yes?

OK, then I think I have a plan. See, part of my error was planting some at one end of the bed, planting others at the other end of the bed, and then failing to return to finish out the bed. :) The Gardening Partner really, really hates interplanting, so the two groups of leeks, with recently-planted snap peas in between, are irritating him every time he sets foot into the garden.

So I'm thinking:

1) Yank and eat the smaller group and extend the snap peas, next weekend.
2) Yank and eat the larger group in time to replace them with bush beans in May, or yank sooner if they start to bolt and tuck in a crop of something fast.
3) Yank the snap peas later and replace them with a later crop of bush beans.

That feels all nicely plan-like. Now I'm searching it for flaws.

That sounds like a good plan :).

If they don't bolt, then they will probably continue to grow until next spring -- is which case they might need the space!

I grow leeks every year, but I have only dealt with them where the seed is planted in December or January and the starts planted out in the early spring. Your summer-sown, fall-transplanted ones are a mystery to me. I don't know what they will do but I am very curious to find out :).

If they do start to make a stalk, I suggest you harvest them immediately. Long before the flower develops, the layers of the leek convert to one woody core and a thin outer covering. You can still use them in stock and stuff, but they are not leeky-textured and tender.

Wait!!!

Just chop off the tops and eat them, then transplant the bottom 1/2 in inch of the stalk, plus the roots to the new location. They will regrow from the stump, and are not likely to bolt once they have been cut back so aggressively.

You can have (halve?) your leeks and eat them, too.