Perennial flowers come back year after year. The advantage here is you never need to replant them. However, short of transplanting them all, you are pretty much locked-in to your original garden design. One tip with perennials is to choose them based on their tolerance of sun or shade. Another tip is choosing perennials in different heights to create more visual impact.
Flower bulbs come back each year, after being dormant over winter months. Most flowers bulbs are pretty strong and reliable so you don't need to really watch them. They just bloom each year. And like perennials, you can plant bulbs according to flowering times for a constant array of color.
Plant your rose garden so they will get at least six hours of sun per day. Eliminate weeds and get some great circulation and these pretty flowers will keep coming around each year.
Check out more flower ideas from Apartment Therapy: