For long lasting flowers, I love zinnias! I grow the shorter zinnias that are about 15 inches high and wide and come in the single and double flowered versions.  I always put them in my planter boxes up against the house. This year I also put them in my my flower bed in the front yard.
I buy starter plants around mid May and they usually are still flowering in the fall. This annual likes full sun.
I can usually find an assortment of different colors in my area including orange. . .
yellow. . .
and different shades of pink. . .
In case you want to grow them from seed, burpee.com and territorialseed.com have nice seed selections.
