The number 1 tip for roses that I received when buying my roses was: Make sure you water them
So, when planting your roses in your newly prepared garden, make sure the soil is completely wet. I’m saying that you should do this at this stage because if you dig the holes first and THEN wet the soil, you might have to dig your holes again. So, give the soil a LOT of water.
You will still have to water your roses straight after planting, though, so don’t go packing that hose-pipe away just yet. 😉