But for those of you fellow nutcases out there who want to persist in gardening in 110 degree heat, the Arizona Victory Gardener is here with a helping hand.
The secret: high density planting in irrigation rows.
--The "high density" part means planting so close that there is solid shade on the ground from the growth of the plants.
--The "irrigation row " part means an row 1-2 feet wide (however long you want it), that you flood with water, once a day.
Using this method, you can keep your garden plants going ALL SUMMER long, with the absolute minimum water bill. In the picture above, I have an irrigation ditch with young sunflowers and cucumbers coming up. Yes, the flooding covers them up with water for a while, but they don't seem to mind.
The whole key is keeping the root zone as moist and cool as possible. The dense planting keeps shade on the ground. I recommend flooding your row in the evening, to minimize the water lost to evaporation. Build the berms around your flood zone 3-4 inches high, so you can fill it up with water real deep. One watering per day will be necessary once the temps get above 100.
You can even keep some "cold weather" crops going through the desert summer, if their roots are kept real wet and they are "under-planted" under somthing that gives them reasonable shade.