what causes yellow squash plant flowers to die?

Question

Several yellow squash plants. The new little flowers are turning greyish brown and withering. I am in S. C.

Answer 1

As with squash plants, this is typical behavior. They will produce mostly male (non-fruiting) blossoms early in the season (which normally fall off) and will gradually start to produce more female blossoms as the season progresses. Give it some time and you will see it start fruiting.