Okra, eggplant, peppers (hot especially) all take heat rather well. If you hang a shade cloth--something that lets enough light through but protects from the worst of the sun--it helps. Here in Israel, people plant vegetables in shady areas, too. Frequent watering is not as good as less frequent, deep watering that encourages the roots to go deep. Try double digging your beds, too. You take out the top 8-12 inches of soil, then work compost (water retaining compost, for the desert) into the next 8-12 inches. You return the removed top layer. This is often done in trenches, moving the top layer from one area to the next, then putting the dirt from the last trench into the first. Of course, for containers, this is not the key.

Consider also protecting your containers, perhaps digging them into the soil or putting insulation around them, so the roots don't get too hot. Watering in the evening may also help keep the roots from cooking. Be sure to have good drainage for the containers.