We lived in Saudi Arabia for five years in the early eighties, in a two story concrete town house. Had a small area outside the dining room where we planted frangi pani and had our imported Thai Orchids hanging under a shade. On the roof we had two foot by two foot by two foot high wooden boxes. Some had plants that hung over the side of the roof and had beautiful red flowers. The rest had vegetables growing in them. Average daily temperature was around 125F but the air was very dry so we didn't notice the heat that much.
We had an open house once and invited both the imported workers and the locals to come through and see our flowers, etc. The Saudi's were amazed and oohed and ahhed the whole time they were there. We left Saudi not long after that and sold all the flowers, etc. Took in about $5K American on the stuff, mostly bought by the locals.
If you take the time and do the work you can grow things on cement or rocks. Stick with it T, eventually you will be happier.
George, preparing to do a rain dance in the backyard, we need the water.