Butterfly, I hesitated to answer you because I wanted to see how my double dianthus would grow this year. So far, they are beautiful, just gorgeous but I don't expect they will last more than a year. In the past they have not been perennial for me (long term) because of weather. If we have a rainy summer, mine will go. Last year they didn't mind the heat, but sometimes they do get 2nd year melt out. Depends. I do not know the cultivar of mine, they were just some seed I'd save and decided to see if they would grow. Old seeds so who knows? They look a lot like the ones in your link.