Never mind. The crops all returned to green on the next day. Puzzling.

I am in summer of my third year and I haven't missed any waterings but my crops on the terraces on the east farm have turned a silver gray color (pumpkins, corn, mint, tomatoes, cacti, pineapple) except for one plot of corn. i think all of the field plots are soil fields and the crops appear healthy. Any ideas? The corn plot that is green is is right next to one of the silver plots.