I have humid summers, so black spot is a problem. Black spot is a fungal disease that affects rose leaves. They get black spots, turn yellow and fall off. It can weaken the rose, but mostly makes it look nasty. I use systemic fungicide to keep the leaves healthy and green. You may not have to do that in a drier climate.
My springs are also very wet. We have freeze thaw cycles in February and March. The ground thaws to mush in the day and refreezes at night. It was colder this year, so we just got several feet of snow that didn't melt until April.
You may also want to think about if you are willing to spray the roses for diseases. If you want to grow roses naturally, choose more disease resistant varieties. There are some books about growing roses organically. I gave it a good try for a couple of years, but got tired of blackspot. for what it is worth, the knockouts get black spot in my area as well.
