I bought Colette on sale 2-3 years ago & haven’t pruned or trained her since—just grew her in a pot for 1-2 years with purchased potting soil, and then in my neutral-pH clay soil. For me (Z9a, humid subtropics), she grows like a sprawled out starfish, about 2’H & 6’W, with little branching. Also, she only grows flowers on the tips of her canes. I thought about pegging her, but too thorny. So I’m going to hard prune her this spring, and if she doesn’t like that, then it’s the shovel for her. Sorry, Colette.

Better than average mildew resistance unless extremely water stressed. Very good rust resistance with some black spot showing up late in the season on old foliage. That is in Zone 9b, Central California Coast, nine miles from the Pacific Ocean with extreme marine influence.

No way to know for sure, having not tried it myself or heard of anyone who has, but I think it wouldn't be too easy to deal with, growing that way. A mature plant throws out long, relatively lax canes (10'+), which readily take advantage of any upward support they find (I have to spend time keeping it out of surrounding small trees and keeping it on its own support), while the main trunk is still not that substantial, even after some years (unlike Mme. Alfred Carriere, which has hefty main trunks and can be trained to be freestanding). It would be a sprawling, very thorny thing with massive amounts of biomass, I think (maybe cascading down a hill would work?). Its response to pruning is vigorous production of more long canes so I tend to cut a cane off entirely if I want to stop it from going some direction.