Biology

Sunlight contains all the colors of the visible light spectrum, from red to violet. Each color of light has a different amount of energy. Light is wave energy, thus each light color has a different wavelength. Red light has the longest wavelengths and the least amount of energy. Violet light has the shortest wavelenth and the greatest amount of energy. A combination of all the waves of visible light produces what is called white light. Sunlight and most indoor lights emit white light.

Plants need light to produce food, to grow, to reproduce, and to flower.

But, do plants need all the colors of light they receive from sunlight?

The answer is yes. While some green and even yellow light is reflected from plants, some of these light energy waves are absorbed.

This folloiwng link provides you with the oportunity to see for your self how plants respond to different colors of light. The link provides a virtual lab that allows you to see how plants grow under different wavelengths of light.

http://www.glencoe.com/sites/common_assets/science/virtual_labs/LS12/LS12.html

You will discover that plants absorb energy from all visible light colors. Green and yellow are the least absorbed light colors, but they are not totally reflected as thought. Scientists are using LEDs to investigate the effect that different light colors as well as combinations of light colors have on specific plant functions.  For example, using LEDs, red light combined with blue light affects flowering and blue light encourages vegetative leaf growth.