Yellowing Bean Bush Plants

[FarmerSkull]

Thoughts on my bean plants? They're yellowing like crazy. They're getting about 8 hours of sun, from 6:00am to 3:00pm. In the valley here in So Cal, we've been having 90 degree days, repeatedly. (Had to add artificial shade for my lettuce that'd wilt daily).

But I'm not sure what is going on with these bean plants. They yellow and the leaves fall off. I've had them for about 3 weeks. They had maybe one yellow leaf when I brought them home, but the yellowing continues. I've watered every third day probably ,with good drainage. I check the soil to make sure its no longer moist before watering again. Been using a 3-1-3 fert every 7-10 days in quantities as directed.

Thoughts?

[FarmerSkull]

Green thumb guy said too much water. It hasn't been that much, I didn't think, but I'll let it dry more...