A friend has asked me what this is in her garden.
Apparently it's going mad! I have no idea...does anyone else know?
edited August 2020
and welcome to the forum
It looks to me like an amaranthus, possibly from birdseed ... now often grown as a veg ... it's one of the so-called 'superfoods'.
Gardening in Central Norfolk on improved gritty moraine over chalk ... free-draining.