I'm super bummed right now. My zucchini plant went from having many healthy leaves and several blossoms just a few days ago to this sad state.
I pulled off most of the upper stem, which had turned to mush, and found at least three squash vine borers. M****rf***ers!!! I left the few relatively healthy remaining leaves out and covered the ravished stem with some soil in the hopes that it can put out some more roots and recover. I also planted a few new seeds as insurance. I know it's super late, but we could have two full hot months left, maybe I'll get some zucchini in October.
We'll see if it's able to make a comeback. I'll post an update in a few days.