Roses can be addictive.
Our gardens are often, in a sense, an artificial environment where we provide water and nutrients that are not provided by nature. I get no summer rain, yet in some years we get as much as 40 to 50 inches of rain in the winter months. So, I have to provide water during the dry months to have a vigorous plant. However, some HTs will survive without the water. They won't thrive, but many won't die, either. So, to me, it depends on the rose.
Smiles,
Lyn