Question
HI!
I live in west central Texas and I have always had roses around.  Most of my roses have come from cutting from other plants of friends.  
Last year and this year both I tried buying a climbing don juan rose in a poly bag while it was dormant and planting it in my yard. (I two separate locations) Last years died, and I assumed it started while we were on vacation and the neighbor boy we hired to water didn't water it enough - it began dying from the bottom up..
I tried again this year with a better location and it began growing wonderfully.  It has been in the ground a couple months.  It sent two shoots up about 2.5-3 ft. and several other smaller shoots. Then a couple weeks ago I noticed the smaller shoots drying up and dying and now the main branches there when I bought it are nearly all black/dark and the largest shoot is really the only thing that looks alive, including recent new leaves that are still a little reddish and immature.  We have had plenty of rain this season and I fertilized lightly about a month after planting.
Is there something I have missed or done wrong? They both have died from the ground up and had different histories....

Answer
You haven't done anything wrong. When you buy a rose and look after it well and still it does what you describe, then it was never a really healthy rose to start with. Your rose has got rose canker which means bacteria got into  a wound in the canes and they have continued to make it die with infection. You mentioned the rose was in a poly bag. Many times these roses are reasonably priced because they are bought after the wholesaler has sold the good, healthy ones. It is sort of like gambling sometimes thy grow very well but many times they get rose problems.