I saw this post while looking for information on another hypericum I just learn I have - Great St. John's Wort - a native perennial. There are some of Hypericum kamianum around the University of Minnesota St. Paul Campus. However clearly those are hard to find - I couldn't even find any outside the university campus so I bet most gardener list them as hard to find. I'm envy of some of the species at the Minnesota Arboretum - I wish I have some Anise Magnolia - the leaves smell that way when you bruises them!