Quite a few of my neighbors gave up there garden weeks ago. The Texas heat was just too much for their crops. They are astonished that my garden is going strong. I'm a newbie, so I guess it could be beginner's luck. But I'd like to think that there are two other things working in my favor:
1. Drip Irrigation - we bit the bullet and spent $100 to install a drip irrigation system connected to our sprinkler head (I'll do a post of how we did this when things slow down). This was a great decision because all of our water is beging applied directly to the root of the plants. The plants are covered with 2 layers of newspaper and about 2" of straw mulch to help keep the ground covered and moist after watering. I water every other day for 30 minutes. The emitters are set at about 2 GPH --- this is a guess, I'll test before making my drip irrigation post.
I would gander that overhead sprinklers/watering do a far less efficient job at watering the roots of the plants. Watering leaves aren't much of a benefit at all; especially leaves of plants that you don't eat.
2. Crop Selection. I knew these crops were going to be grown in the heat of summer. So I selected crops that could handle it. Squash, Corn, Eggplant, Zucchini, and Cowpeas (the only pea in the south :) ). All of these were planting in July when temps were already over 100 and were headed to 110. We've been over 100 for over 50 days in a row now. The eggplant should start to fruit just as temps should lower to the mid-80's. Temps are already lowering back to around 100 and should be in the 90's pretty soon.
So I just wanted to share the two ways that I have found to beat the heat. Of course, when you plant crops in the spring, you have no idea that the summer will be 110+. So next year, we plan to have shade structures ready and use taller crops to provide afternoon shade to shorter crops.