When do leeks go to seed?

As subject really. I still have a lot in the garden, how long before they look picturesque like swans? I dont want to waste them. I can see a lot of leek n potato soup happening.

I'd give them until late March/April, when the weather begins to warm up. You can still cut the flower stalk out of the middle and use the rest in casseroles etc. when they do go.

I'm getting a lot going to seed already, (I'm putting it down to a dry year last year)
Still as DD says, they can still be used. Leek & tatty soup on the here tonight.
In fact, I haven't bothered taking it the middle this time.
 

I had loads go to seed last year (still good for soup though)and so far this year only the one.  The same variety, Musselboroug but there seems to be no rhyme or reason for them going to seed.  Just keep your beady eye on them  :blink: and use them as you see them start to  'thicken' up