I'm very confused. I would like to plant some Thalictum flavum subsp. glaucum (they have yellow flowers) in the back of one of my flower gardens. First, I can find only one place in the US that sells them. 2nd, my confusion has to do with what zone they will grow in. Some sites say they will grow in z3, other sites say they are hardy to only z5 and one site said only hardy to z6.

Is anyone growing these plants? I hate to spend the money to buy them only to have them die out in winter. I've already lost several plants, like my black-eyed Susans after the awful winter we had.

Also can anyone recommend a Canadian nursery where they might be available?