I talk in Psychology for Designers about the tension between art and science in design and how 99% of the time the science backs up the art.

The poet Goethe described the psychology of colour two hundred years ago only for science to come to eventually come to the same conclusions hundreds of years later.

He describes Green as:

The eye experiences a distinctly grateful impression from this colour. If the two elementary colours are mixed in perfect equality so that neither predominates, the eye and the mind repose on the result of this junction as upon a simple colour. The beholder has neither the wish nor the power to imagine a state beyond it. Hence for rooms to live in constantly, the green colour is most generally selected.

Read more of his musings at Goethe on the Psychology of Colour and Emotion on the wonderful Brain Pickings.