You really might want to contact Steve Horan in Woodbury ( Horan's Daylily Garden) , Kyle Billadeau in Chaska ( Turtle Rock Garden) and Kathy Lamb ( Loon Song Garden), all of whom live in Minneapolis suburbs I have personally visited their gardens several times. All of them have AHS Display Gardens and their contact information is listed on the AHS website. They all grow spiders and Unusual forms and would be really great resources as to which plants would be hardy in your climate. Kyle and Steve grow some of Jim Murphy and Margo Reed's daylilies, Kathy grows quite a few of Dottie Warrell's and also hybridizes spiders and Unusual forms. I think they all sell from time to time also.
