Hi BThomas,
Firstly why are these roses planted by grape vines, "well here in france they grow a lot of grapes for the wine trade and eating "but" its a big part of the french culture,
Now offten while driving passed these vast fields of long lines of grapes you'll see at the ends of each row a "Rose"
plant just growing away alone
why?
Well these roses are the first place the bugs will attack and this sign show's the grape grower what's infested his vine and it's spraying time,
It's a much better way to deal with the verious bugs pre the vine being covered with bugs, An early warning device "natures alarm you could say"
Clear away all the grass etc away from the complete rose's now! both the ground area and all top area's so you can see whats happening around the complete rose,
Then prune all the dead off the rose (do this by cutting an outward facing cut from a nod ) And slightly above the nod, this allows the rain to run off the plant and not soak into the good wood of the rose and we're you've just cut, (Google rose pruning to see how to prune)
The idea of removing the dead wood is so the rose can give all it's growing strength to the good wood and to stop decay, If any sign of green fly can be seen then spray the rose, you can get purpose rose bug sprays but as a short time method use used washing up liquid ,cool water not hot, just spray all the plant, Pay attention to under any leaves, this is the place bugs live,
Now feed the rose with rose feed or tomatoe feed is much the same, and ensure the vine is kept off the rose and the Rose's have plently of light and space to grow,
continue to water to aid the plants roots to settle, and feed once a week with a weak feed, you'll soon see the plants change and new growth will appear?
Ps roses can last for a very long time if looked after, 80 to100 yrs.
Hope this helps and good rose growing,