Into October now, it is already getting late, but perhaps a reminder for next year–fall is the other good time to start a food garden in the desert.
You will probably not have much success with foods that need to flower and fruit, but for leafy greens, this is a great time.
Chard, spinach, beet greens, herbs, all these can still be planted in the desert in October. Of course, they will need hand watering or irrigation. But some will produce right through the winter, depending on your location.
Some will go dormant, then revive in late January and February, when the longer daylight and warmer temperatures begin to return, the time when you can begin adding your regular spring vegetables.