I am glad you wrote this great article to let people know about these beautiful plants! I am in zone 4, and it is hard to believe that they come back year after year here too! The first couple that I planted didn't come back the next year, so I thought that they might not be hardy here. I enjoyed them so much though that I planted a few more that year,and figured I would still enjoy as an annual. I have now enjoyed these same plants for 3 years, and they are more beuatiful each year! So don't give up if they don't make it the first try!
Great article, Lee Ann. Right now in my garden the temperature is near 0 Fahrenheit, and my hardy hibiscus are buried under about three feet of snow, but I have no fear for them--they will return. I also don't give them any winter protection. They are quite easy to grow from seed, if you can find the seed--not that easy to find. As you pointed out, they come up later than most perennials, well into June for me, but then they grow very fast and bloom by August. One summer when mine were young, I dropped something heavy on one of them and broke it right down to the ground. I thought it was done for, but sure enough the next summer there it was, completely forgiving of its bad treatment. A wonderful plant!