[mdjlucan]

Can anyone put a name on these two weeds growing on my allotment

[Gardener and Rabbit]

The first photo looks like buttercup.  The second photo looks like a clump of shallots, or some other member of the onion family, probably left over from a previous crop.

[mumofstig]

Your weed post was merged with the weed? thread here
http://chat.allotment-garden.org/index.php?topic=75018.msg1439482#msg1439482

and you have an answer, there, as well 

so I'll lock this one.