I wanna put in my $0.02USD in and recommend mulch, too. Mulch around it. That way, when you water, the mulch will help keep the soil moist (but not soggy) and keeps the ground cooler.
I've transplanted many roses wrongly and, if they're meant to live, they bounce right back. Give it a week at least. One thing *I* like to use when transplanting mature bushes is Age Old Kelp (
http://www.ageoldorganic.com/2...). I can get it locally at a LGS. You can also use SuperThrive (
http://www.homedepot.com/webap...) which you can get at Home Depot. I transplanted a few weeks ago 9 roses from the west side of my yard to the east side & all survived no problem.
As far as burying it, I'm of a firm believer of burying the bud union a minimum of 2" below the ground surface, then mounding dirt UP over it so that just about 4" of the canes are sticking out.
