West Midlands,
United Kingdom 
Bought from a plant stall last year, no name, looks a bit like Liatris but isn't! Tall flower spikes, bright pink flowers, bees love them. Flower spikes about 15cms on bright green stems, leaves non-aromatic, in pairs. Also spotted it growing by the river bank where it's much taller than my potted one. Absolute must for the smaller bumblebees who come out even on dullest days for it!
21 Jul, 2012
Answers
As above...purple loostrife. Water loving, can be invasive but i love em !!!!!
21 Jul, 2012
Thank you both so much! I love anything that bees will come to so I'll be on the lookout for more. I take your point about invasion but in a pot that won't be a problem.
21 Jul, 2012
You can grow it easily from seed. I bought a variety called Dropmore purple from T&M and i got hundreds of them !!!
21 Jul, 2012
Lythrum salicaria. There are lots of different very similar forms.
21 Jul, 2012