Enjoy yourself. Look at the surroundings with new vision and experiment. Except for summers that South facing wall can be used to advantage. Zinnias? Go for Salvias they love the heat, Zinnias wont take it and you will have a hard time. Marigolds also require less water. Think of plants that don't want much water until you can rectify the micro climate. There are some beautiful flowering succulents if they catch your fancy. Then there are flowering cactus also. Citrus various types also love heat and can help in changing the climate.
Regards,
Arif.
