Is this a plant or a weed?

It looks very much like a weed Frenchbean. bit concerned that because of its size and colour it could be knotweed which is very invasive and difficult to eradicate. Does it grow very quickly and have frothy white flowers in a panicle?. Try googling it. Hope Im wrong

You've given me a starting point -thanks for that Mageth.

it isnt japanese knotweed, it doesnt produce seed as the victorians only imported the female plant. is the flower spike in the picture part of the plant? as yet know idea but i will see if i can find out.

Yes the flower is produced by the plant and then later a cluster of deep purple berries appear. I've looked at images of Japanese knotweed on google but I'm not convinced it is that, the stems look similar but the flowers are different.

is it a 'Pokeweed' the flower is similar?

BINGO!! Just googled 'Pokeweed' and thats it - THANKYOU Seaburngirl. It's says that they are edible and also poisonous if not cooked properly so I won't be trying that! Now do I kill it or keep it?.....

as it is so statuesque i'd always keep a bit and compost the rest. i always keep an odd plant if it does something usual. [glad my memory was ok but cant remember its latin name]

Think seaburn is right. on this new photo you can see that the leaves are longer and not heart shaped like the knotweeds. Sorry for any panic

oops got there brfore me

The latin name is (Phytolacca americana) according to Google.
I think I will keep some but most will have to go as they are growing in all the wrong places. Thanks to you both for helping me!

I was told once that a weed is only a plant in the wrong place!

Unfortunately I have an awful lot of 'plants in the wrong places' at the moment Chris.

A weed is something you dont like! lol