The roses like the sun and fresh air. For roses in the open, out of greenhouse, the south sides of the walls isn’t suitable at all, because those places tend to get too hot. If it’s imperative to grow the roses in such locations, the red varieties ( which like the sun most ) should be chosen. The ivy-like roses are perfect fit for such conditions. Also, the pink or white roses can be planted.
While growing roses in a greenhouse, light is the one of the most deciding factors. The light intensity is much higher in summer, because of this the roses grow much faster. The duration of daylight has no effect on the flowering or growth of roses. The research shows the high intensity (100 W) fluorescent light boosts the production of roses by %50 to %200, especially for the roses of short-stemmed variety.