So, I don't live in your climate, and I am not a rose maven, but no one else is answering this. I did live in Tempe AZ for a while, so I know it is hot there. I would really want to do something to keep the roots cooler than they would be in their little pots. I am not sure what a band size is, but a one gallon is not all that big for a rose. I would consider including a nursery bed area in your landscape plan, and putting them there in the ground. If you have to pot them up, put them in the next largest size container and then sink them pot and all into the ground somewhere where they can be cooler at least until late fall. You could dig them up and move them around as work progresses. There is an assisted living with a lot of landscaping near me and they grow some not-so-hardy varieties of rose here by doing exactly this, and then lifting and storing the pots in their cistern during the cold winter. You could do the same thing with your plants.