We have over 100 roses here at Casa Rosa, mostly consisting of old garden roses. Since we now have 2 acres to spread out (though only about half that is full sun), I have been growing more and more once bloomers.
The roses are dispersed through out the garden, but the main concentration of roses is in the aptly named Rose Garden and Potager. I have mixed different types of roses along with perrenials, bulbs, annuals, vines, and other shrubs to ensure a longer period of interest. I also think it is healthier for the garden to have diversity and it makes a more interesting garden.
I focus primarily on organic solutions in the garden and avoid the use of pesticides, insecticides, fungicides, and herbicides. I have been known to cave in and use Round Up on poison ivy and the seemingly unstoppable wire grass.