I am only a dillatante gardener, but: roses generally take a fair amount of fussing, even the relatively low-fuss varieties. Water, bugs, powdery mildew, etc.

I *think* that if you get heirloom types you'll have less trouble-- but check with those in the know. I decided I wanted complete abscence of trouble, and went with rosa rugosas, which take abuse of all kinds.

Here's a list of easy things to plant that will flower in succession -- from gardening junkmail which I got earlier this year:

"List of flowers that will have something blooming successively throughout the growing season:
crocuses*, daffodils*, tulips*, lilacs, peonies, roses, tall garden phlox, daylilies, asiatic and oriental lilies, coreopsis, black-eyed susan, tall sedum, asters, and mums."

(*Clearly for northern areas that get below freezing in the winter.)

They didn't mention daylilies, especially reblooming ones, but they should have. Oodles of colors.