NASA scientists have learned that plants on other planets may be yellow, red or green, but are not likely to be blue.
Plants on Earth absorb blue and red light but little green light. More red light reaches plants on Earth, and blue light is the easiest for plants to absorb. The colors of reflected light are the colors we see when we look at something.
On other planets different colors of light may be more likely to reach the ground and the plant life there.
Here on earth plants commonly found in low light areas like jungle floors have purple undersides to their leaves. The coloring helps the plant to reflect red light back to other parts of the plant. The light hits the green part of the leaf. Then it goes through and hits the purple part of the leaf. The red light is reflected back up to the green section. These ones make the best low light house plants.