In its lighter shades, it's a cool, calming color for most people. Green also is a calming color, and is the most restful color for the human eye. Moreover, some studies have shown that people who work in green environments have fewer stomach aches. Not only that, but suicides dropped 34 percent when London's Blackfriar Bridge was painted green. In Celtic myths, the Green Man was the God of Fertility.
Chickens wearing red contact lenses are happier, eat less food, and lay more eggs.
Except for blueberries, nature does not create blue food.