Question
Many years ago I was told that if you buy a rose with a metal tag on it to take it off because it will eventually kill that cane.

My husband got into welding rebar (steel) so I had him make me a trellis for my zephirine drouhin climbing rose.  It is not doing well.  I got to thinking about what I heard years ago.  Do you think that is what is going on with my rose?  

I moved it into a well amended hole.  ($5 plant into a $50 hole)

Answer

one of my fav roses   No
Something else is happening.
could be anything maybe you planted the wrong variety for that area? see any one else with that type roses around where you live?
another problem could be if it is near a lawn. The high N of the lawn fertilizer is bad for the roses.
Also if it is getting watered over head
BTW
what are you feeding it?
Use Compost?
try feeding it a good organic rose fertilizer and see what happens.
any signs of pests or diseases?