Roses are fairly thirsty perennials. Most varieties should be watered deeply twice per week, receiving an inch of water in each session. Of course, if your area is experiencing rainfall, Mother Nature takes care of the watering needs for you! Water your roses early in the day, to avoid fungal issues or molds. Morning watering helps decrease the opportunity for mildew to set in, because the roses can dry out during the day before nightfall. Always water at the base of the plants, instead of the petals or leaves.