Rose petals are edible, and rose hips make good tea and are high in vitamin c. I always plant a few marigolds along with basil with my tomatoes, and sometimes a few carrots.
Violas are also edible, and so pretty.LOL
There are a lot of edible flowers, but you wouldn't want to make a meal out of any of them.
Besides. I don't particularly like roses. Stuff gets snagged in the dark.
/johnny