Hey Hon!
Here's some info on the New Dawn
rose:
http://www.ces.ncsu.edu/depts/hort/consumer/factsheets/roses/climbingroses/newdawn.htm I have one. I consider it a climber, not a trailer, although it really does both. Mine only bloomed once in the
spring, but wow, what a show! It grew quickly , too. But when we moved it to make room for a houseaddition, it almost died on us. We had to cut it way back and are now nursing it back to health. I think if it hadn't been moved, it would have been just fine. Neighbors of our have one
growing onto and completely covering a large arbor. The thing's at least ten years old and just plain gorgeous.
Maybe someone else has an opinion on how it would do in a planter. I don't know. My uneducated guess is that it ought to do just fine, given proper drainage.