rig shade above the plants.

Thank You....Jean001a......What type of material should I use....White Sheet or Blue Tarp ?

I have one plant that is doing this as well. Earlier I thought it was a disease issue and almost pulled it. The plant has continued to put off new suckers and new fruit clusters but as soon as the sun rises it looks like a rag doll but then perks up after sunset.

Anyone know what causes this?

It's a normal reaction to the heat. As the plants get older and toughen up, it will happen less. Just make sure they're getting enough water.

I imagine that all the white vinyl just means more light, which leads to more productive plants.

Sounds like the excessive heat is causing the wilt.
Heat reflecting off the house is overheating them.
You can just leave and make sure there ie water aplenty.
If you want to shade them then buy shade cloth .

Probably heat refection off the house.
IF the plants are in good soil in the ground and watered very well which in this heat (100+ degrees)should be twice a day then they really shouldn't be wilting.

As long as the roots are large, no disease, good drainage, well watered then no wilting should really occur even in 105 degree temps.

Mine have yet to wilt this year and we have had over 108 degree temps.
I have one branch wilt the past 2 weeks only because a damn squirrel jumped up into it and broke that branch 2/3rds in half, only 1/3rd of the branch is supplying water to that whole part of the plant and it has about 20 tomatoes on it.
It wilts when over 95+ but is still hanging in there.

All the rest of the plants and rest of that plant never wilt at all though. and that fact tells you it is the lack of water supply doing the wilting.