Kelli ...
The schedule and timing I described in my post is what works in my climate and my soil. You will have to experiment to find out what works for you. I just wanted to show you how much water a rose needed in a hot and dry climate.
Since you live in southern California, you will probably have to water all year. I think it would be more water wise and less labor intensive, if you can afford it, to install a drip system for your roses. They will need more water during the high heat periods and it will have to be adjusted for the other seasons, but it won't be so much work for you.
Not all leaves are equal for mulch. Some mat horribly and inhibit water from reaching the soil. (Oh, and if you buy commercial compost or soil amendment, you want to avoid anything that has a lot of peat in it because if peat dries out in an arid climate, it is like concrete and will block all water from reaching the soil. I use it as a weed barrier under my rock borders. It's wonderful for that purpose ..
) Also, some leaves decompose very quickly in high heat and you are constantly having to replace your mulch. If you mix pine straw ... you often can get it at garden centers ... or even regular straw with your leaves, your leaf mulch will last longer during the summer months.
As for organics ... they are wonderful, too .... keep in mind, high temps in an arid climate use them up faster than in a more humid climate, so you need to feed the plants more often if you are using organics to feed your roses.
Good luck with your roses.
Sue ... thank you for the heads up about using wood chips for mulch. I hadn't connect those dots ...