Was the photo taken in the UK? I'm thinking of Cirsium vulgare, Spear Thistle, as about the only candidate if it was, although the leaves are a little atypical judging by what is visible in the picture.

Yes, it was taken in the South of England. I did look at spear thistles as an option but I haven't seen an image of one like that yet. It was a big plant, over a metre tall but didn't have any spikes. Thanks for post!

It is certainly a bit atypical but I can't think of anything else it can be if it was in the wild. Even in a garden I can't think of another possibility.