Gary, I'd like to add a couple of thoughts to this conversation - whatever you do choose, if you're planting them this summer it's already very hot and new plants won't survive without being watered. Even if you can just lean out the window (like you did with the camera?) with a watering can or two, that will help the new transplants to survive until the days get shorter and cooler. They will need water every day until the weather cools off. By next summer they should have grown some good healthy roots and be more drought tolerant. But that doesn't mean they'll survive and look nice if it doesn't rain in July for 3 weeks.
Also, all gardening is eventually an exercise in trial and error, so you will probably find the plants that suit that area best by trying several at once. Keep the ones that thrive and remove the ones that get overwhelmed. If you want to have just a solid flower bed of flowers, you want the lustiest flowers that WILL spread somewhat and shade their own roots in the hot weather so you don't have to weed and water. It will look a lot nicer for most of the summer if you have to cut back flowers that are growing a bit too big, rather than having to weed and worry over small struggling plants. Go for the vigorous ones! Much better chance of success in this situation.
