Britannica Sources used in this answer

Why do many plants appear green?

Created from Britannica articles using AI. AI can make mistakes, so verify using Britannica articles.

Diagram of a tree leaf illustrating photosynthesis, with arrows showing sunlight, water, and carbon dioxide entering the leaf and sugars and oxygen being produced. A person is shown beside the tree to demonstrate the exchange of oxygen and carbon dioxide between plants and animals. — photosynthesis Diagram of photosynthesis showing how water, light, and carbon dioxide are absorbed by a plant to produce oxygen, sugars, and more carbon dioxide.

Plants appear green primarily due to a pigment called chlorophyll, which is found within the chloroplasts of plant cells.12

Chlorophyll is essential for photosynthesis, the process by which plants convert light energy into chemical energy. This pigment absorbs light most efficiently from the blue and red portions of the electromagnetic spectrum. Because chlorophyll does not absorb green light effectively, that light is reflected, which is why plants appear green to the human eye.134

While plants may contain other pigments, such as carotenoids, chlorophyll is typically present in such high concentrations during the growing season that it masks these other colors. These other hues only become visible when chlorophyll breaks down, such as during the autumn season in deciduous trees.12