Rose support design process
The rose support has been built (well, almost finished) so you've seen the final design. As I've said I really didn't have a good idea of what I wanted to do, so after I set the two posts I got to work on the computer.
The first design was the simplest: just add some horizontal members to the vertical posts. This would give me something to tie the rose canes to, but almost immediately I knew this was not adequate. Sure it would be easy to build, but I knew I wouldn't be happy with having to tie many rose canes to it. Plus it wasn't really my style.