1) Try a shade cloth 24/7 for hot months.

2) With containers the roots may be getting too hot. Try shading the containers. Set some in-ground (with or without pot) as a check.

3) Consider your soil and fertilizing practices. Heat may not be the only concern.

I second : Shade Clothe:
60+ days temps around 100F: Full sun all day ...That is a lot of heat.
Check the regional gardeners (Texas Gardening) forums and find out how they are doing.

Here is a link that might be useful: here

I found lots of water, lots of compost tea and adequate calcium, and only morning sun or shade cloth worked best in my containers. I have/had lots of peppers, but they did do better in the greenhouse when the nights get down to 40's. We had over 3 months of 100 degree weather or real close this season. I started peppers in November and had them good size before, after a greenhouse heater failure today, will be starting peppers late this year.

Also, keep an eye on springtime temperature forecasts. If the overnight forecast is for below, say ~39f, then move your plants to safety. A lot of us move our container plants around in the spring and fall, for temperature reasons.

Otherwise everything else previously mentioned makes sense imho. I've read a lot about hot climate gardening. It seems that everyone is either using shadecloth, or planting in areas that are shaded during a hot portion of the day. You could frame it up using flexible pvc conduit, like a hoophouse for instance. You would fasten shadecloth over the top, and leave the sides open. You can always remove the shadecloth if there's extreme weather in the forecast. The PVC conduit frame can also double as a greenhouse to extend your growing season. That's just one idea, but you may discover better alternates upon researching the topic.

Good luck.

Steve

Here is a link that might be useful: Inexpensive Hoophouse's on YouTube

This post was edited by sjetski on Wed, Dec 11, 13 at 10:20