I've been using Epsom salts to encourage growth on China and Tea roses for the last couple years after reading about it's use for roses in general, in a British gardening book
The standard amount for an average sized rosebush is 1/3rd of a cup of Epson Salts dissolved in a gallon of hot water and then cooled, given once a year in spring.

Be sure the ground is moist before you add the epson salts. I mix in a bit of 12-12-12 fertilizer for small rosebushes, and 16-16-16 for those that are more than 4' tall, and climbers.
I had amazing success with this for getting Le Pactole, and other Teas to get a move on. Before Epson salts Le Pactole bought as a band sized plant in spring of 2011, grew less than a foot in its first year in my garden despite wonderfully amended soil and all the love and praise I could give it.
In spring of 2012 I gave it a couple T. of Epson salts with 12-12-12 fertilizer, after I saw that it tolerated this well, I repeated this six weeks later. My Le Pactole' doubled in size over an 8th month period.
Le Pactole is one of the' slowest to build size" Old Garden Teas.
Now, on March 31, 2013 it is waist high and almost as wide,
Oh joy!
I gave Epson salts and fertilizer as stated above to Monsieur Tilllier and my plant bought in January 2012, as a gallon sized rosebush from a.r.e, grew to be 4 and 1/2 feet by September of the same year. My neighbor bought the same cultivar from a.r.e 2 months earlier than mine and her plant is still c. half the size of mine, on March 31,2013 and she has excellent soil and cultivation methods and means.
Best wishes for lovely roses,
Luxrosa

Lux, you want to do a soils test before adding Epsom Salts to roses. It seems to be working OK for you -- but it turned out that our soil/water already had a lot more of that than was benign, so adding it did more harm than good.

Since then, we have saved a lot of money, not buying Epsom Salts.

Jeri

Both should be fine in zone 7. JBS is a China and they do grow every which way.

I've had both and still have my four Le Vesuve, but Jean Bach Sisley didn't seem to like it as well here and is now gone. I've found that alfalfa meal tends to make almost any rose grow larger, but in my hot garden I've also learned that most roses will languish without adequate water and mulch. I tended to underestimate the mulch part but now work much harder at it and have really seen a difference. With porous soil like mine I believe it's really essential.

Ingrid

Le Vesuve is thought to be a tea, or a tea/china hybrid, or a china - there is a difference of opinion. In any event, it likes sun and warm weather. It is normal for it to put out canes in all directions. It builds up dead twigs and canes underneath it, to support it getting LARGE. Here is a pic of what turned out to be 2 Le Vesuve bushes in my garden. Mine did not like to be pruned, so I just did enough to keep it off of the path.

Jackie