[maizey]

any ideas why my leeks have all gone to seed over the last two weeks?

[mumofstig]

Hello and welcome to the forum.
I don't know where you are (could you put your location in your profile please ) so this comment may be absurd if your climate is very different to mine.............. but has your soil dried out like it has here.

They will bolt if they've been stressed, which is usually because they are dry at the roots.

[brokenglass]

Mine, Central Scotland, have all bolted also, the 30 or so I gave to another Plot Holder haven't.     Maybe my meanness in always planting closer than recommended is the problem but they are in a good well manured and fed raised bed.

[jaydig]

Some of mine have bolted this year, a problem I've never had before.