I agree with the sweet peas. Gorgeous purple flowers. I too like to plant what I can eat and I find that by planting yellow crook neck,acorn, butter nut and other squash and zucchini, I can saute the big male flowers(they're the ones on the longer stem, farther away from the vine) in a little butter and olive oil after a light drench of egg wash and dusting with cornmeal/flour and seasoning mix.. Nasturtiums are both colorful and delicious on salads. Rosemary planted around the perimeter, especially where you might brush up against it as you're working it releases a wonderful scent. Lavender and sage are beautiful and smell and taste great too. Sunflowers are easy, they look great as a cut flower and if you let them go, provide food for bees and birds.
Marigolds are very good for repelling insects. You can use the flowers as plate garnish and save the seeds on most of these flowers for next year!