Published: 2 October, 2003

Grass absorbs all other colors, leaving green to see

Why is grass green?

Surprisingly, grass has a green color because it absorbs all other colors except green! That may sound odd, but remember that if you can see a color, then that color is reaching your eyes. For that to happen, an object needs to absorb (keep) all of the other colors of the rainbow and reflect (not keep) the color that you see.

Grass and other green plants have a chemical called chlorophyll (KLOR-oh-fill), and its special structure allows it to specifically catch blue and red light. All light has energy, and chlorophyll absorbs the colors that have the correct energy to help power the plant's machinery. The plant can then turn carbon dioxide and water into glucose, a sugar. The leftover light, mostly green, bounces off and reaches our eyes; since there's a lot of chlorophyll in plants, we see them as being green.

The colors that our eyes can see are only a small portion of all the light that's really out there. If you're interested in learning more, I suggest reading about the electromagnetic spectrum, a fancy name for all the types of light. You'll learn about things like infrared, ultraviolet, x-rays and radio waves, some of which may already sound familiar. Ask your teacher and he or she can point you in the right direction. But keep going! We're all a little green at first.