Dorathy, I am in 5/6, Curt Hanson is in 5. I know Gary Shaben (sp?) grows a lot of Curts in Minnesota (I think that is where Gary lives....)
I don't think they would have a problem. If there are particular ones your interested in, and your not a member of the AHS robin, I can post a question there for you.... surely someone in zone 4 grows Hanson's!
