I vowed to tie up the stems of the Clematis durandii as they grew taller this Spring. They don't know how to hold on by themselves and they flop eventually if I don't tie them. I kept them tied until last week when I missed five days while most of the stems added another foot and buds. Curses, some of the stems flopped. It's tricky to straighten them up and tie them without breaking them. I tried, I tied up most of them but broke a few too.
This has been my most conscientious Spring ever and some of the stems have reached the top of the trells--first time ever. Someday, some year, I'll tie them up so regularly that the trellis will have flowers from top to bottom and side to side. Oh, joy!