There is a blue form of Lupin arboreus, the Tree Lupin, I have had a self set in my garden but last winter about killed it off although I found a small root survived it hasn't grown. I have however got a self set in the front garden growing which apparently suits it better, it's currently about 6 feet tall! No flowers on it yet though, it started to grow last year and has really taken off this year with a vertical stem and side shoots coming off at about 45 degrees. I just took some photos so will download them and post them later. The young stems are purplish like yours Lynn, the leaves look the same maybe not quite as blue but colour can vary in different conditions.
I had a photo of the fowers once but must have lost it in my 2008 computer crash.
http://www.robertsplants.co.uk...
There's a white form too!
http://www.plant-world-seeds.c...
