Many years ago I saw this flower for the first time in a display garden at Old World Wisconsin. For me it was love at first sight. I asked the staff member working in that garden if she could identify it for me. She could not. Fortunately, on that same visit to Wisconsin we spent time walking at Boerner Botanical Gardens and it was growing there with a lovely identification tag.
Since then I have always had it in my garden. Asclepias tuberosa or butterfly weed is a North American native. Once established it is late in breaking ground in the spring. It does not like to be transplanted. But it grows easily from seed and the second year and each year after it becomes more vigorous, though not invasive. It lives up to its name, attracting butterflies and hummingbirds as well and even stands up well in a vase.