You know, I had the same thing happen to me with my bush beans and with my asian beans. I don't know if I'm right or not, but suspect that like tomatoes, bean pollen is only happy when the temps are cooler. I'm interested in what the others here have to say.

I'm getting blossom drop on my long beans, which are heat lovers. I think it's way too hot for bush beans. Maybe replant for a fall crop.

try yardlong instead they do great in the heat....

Our first crop of bush (blue lake) green beans were great. Now, hollow stems and curved, tough beans. Why? I know they are getting enough water and our heat here in coastal Texas hasn't peaked? Unusually poor crop.

I have noticed the same thing with some but not all of my jade beans. I think the secret is too pick 'em young as it seemed to be the largest ones that had the woodiness.

My hericot verts (French beans) are still nice, though. Now I will have to try the yardlong beans. I tried some purple string beans last summer (they turn green when cooked) but they just shut down once the heat was on.

Perhaps there is a variety of bush bean that does better in the heat?