Be patient with this one.
"The thing about this plant is that once it takes root, even if it has a terrible season and dies back, the root will live, and it will keep trying again every season until it succeeds. The first year I got two tiny plants out of the bunch that died. The second year they surprised me by coming back. One was potted and struggled until it died back, and the other was in a raised bed, where it sent up two weak stalks, was attacked by a black fungus(?), and died. This year they both came back, and I put the potted one in the ground. The season has been cool and wet (unlike last year), and they've been thriving. The one that had been potted has started sending up new shoots. They're thick, lush, branching well, and the one in the raised bed is blooming. I'm thrilled, if perhaps reconsidering their locations (mistakes were made . . . if I'm going to move them I should probably do that very soon). Wonderful plant, but not for the faint of heart."