In Ray E's Nov. 6 post he shows two different butterfly weeds in his yard.
Here's another plant marked butterfly weed in the garden center. A reminder to look for the scientific binomial name. I thought the plant I bought was the Asclepias tuberosa and that it had died. These beautiful flowers came up and I liked them. Then I noticed the pods.
This is Asclepias curassavica, commonly called Mexican Butterfly Weed, Blood-flower, Scarlet Milkweed or Tropical Milkweed. It is a species of flowering plant in the milkweed family, Asclepiadaceae and native to the American tropics.
According to the USDA plant profile, it is an evergreen perennial subshrub which only grows in CA, FL, HI, LA, TN, and TX. It must be an annual here in PA.
I have saved a number of seeds and, like Ray, I'll see if I can get some plants going in the spring. If successful, look for some at the May plant sale.