What does the long summer mean in the five elements?

The five elements refer to gold, wood, water, fire and earth, while long summer means long summer is coming. Generally speaking, summer begins from the summer solstice, usually in May of the lunar calendar every year. The five elements in May belong to fire, so the long summer in the five elements refers to fire.

The theory of five elements is a kind of material view in ancient China, which is mostly used in philosophy, traditional Chinese medicine and divination. It emphasizes the whole and aims to describe the movement form and transformation relationship of things.