It could be Phlomis?

Thank you Sheilabub, just looked online and they do look similar.. I'll plant some and see what they turn out like.

looks more like a mallow of some sort, possibly one of the wild mallows or M. moschata as a garden escapee.

What are the leaves like? I'd be wary about planting something of this size (and with the amount of seed that it appears to have) without knowing what it is - you could come to regret it. Having said that, it looks familiar but I can't bring its name to mind.

Well there didn't seem to be much in the way of leaves! I'll pop and have another look at it next time I go to St Ives, hope it's going to be a nice plant next year. I quite like mallow...