Just up the street from the blue one was a white one, very similar in
many ways. The tallest stalk was 4 ft. 'Purissima' comes to mind,
but I've never grown it. Looks to have been divided last year, so
individual clumps were small; however, foliage is wide tall and strong.
Looks like a vigorous grower.
Again, was dealing with the same bad conditions.