It strikes me as the sort of thing that, once it flowers, just dies. (No idea why l think that, but l do). If you can hang on until it flowers, which looks like any day now, l am sure there'll be someone along with a positive i.d.
My plant has one central flower spike (although no obvious buds or flowers) that has grown from almost nothing to this nearly a metre tall in a few weeks. The flowers of the nicotiana which I grew last year are from several areas of the plant not concentrated on one spike. The leaves were silvery and furry during the winter and quite thick and leathery. Only now has the 'fur' diminished and the leaf become more leaf-like but huge. When the plant first appeared during the winter/autumn last year it lay flat on the ground and looked similar to a pulmonaria blue ensign nearby. In looking it up under pulmonaria on-line it fit the bill and Lungwort its common name seemed appropriate. Now it has changed.
Posts
maybe wait till it flowers, soon see then.
'You must have some bread with it me duck!'
Gardening in Central Norfolk on improved gritty moraine over chalk ... free-draining.
Something like these?