I live in the south east of England and have three very tall single stem plants appear in a dry corner of my garden which I don't recall planting. At first I though they may be maize and figured that they may have seeded as scatterage for the neighbour's bird feeder.
Then long necks grew which looked like garlic scapes and I thought they must be some sort of onion that I had forgotten. Incidentally crushing the leaves gives a mildly onion smell.
They are now over 6 feet tall (one almost 7) and self-supporting. I am now worried that the tips may not be flowering buds, or be blind and I will never discover what they are.
The person in this thread - https://forum.gardenersworld.com/discussion/994563/identification/p2 - seemed to have the same plant growing, but did not get resolution. Their photo, halfway down shows the maize-like stem off well.
Can anyone tell me what these may be, as I am still on the page of some giant allium?