Light Affect on Plant Growth

For this Science assignment, I chose to find out if the color of light a plant receives, affects the plant growth. Light is electromagnetic radiation that comes in waves, the basic units of which are called photons. Plants use light to turn carbon dioxide into sugars necessary for growth, a process called photosynthesis. Sunlight is a full spectrum of different wave lengths of light. Seen through a prism, this spectrum turns into bands of color: red, orange, yellow, green, blue, indigo and violet.

(Stern, 2004).

The light of the sun is white or a pale color and it is the best for plant growth. I want to do an experiment to see how different color of light affects plant growth. I will use a Red, Blue, Green, and White 60watts light bulb. When I started researching for this project, I read that plants with the white color light shining upon it, photosynthesized faster, than the others.

I picked the colors for my experiment, by asking myself some questions.

The first question I thought about was: why are most plants green? The colors you see are the colors that are reflected from the plants surface, the other colors are absorbed by the plant. This tells me that light in the green range is not absorbed by the plant. That lead to my next question: What if that was the only color available to the plant? Plants absorb light to harness its energy for plant growth and internal processes.

Since plants naturally absorb certain colors from light, and reflect others and plant leaves appear green or yellow because those are the colors being reflected.

What colors are absorbed and how do they affect plant growth? With Green being one of the 3 primary colors I decided to use the other two colors, Blue and Red, in my experiment. My thoughts were if green is reflected, or not needed, does the plant need more Blue or Red.

Light is one of the most essential things used by plants to manufacture food for growth. (Welsh and Cotner, 2012) They do that by converting light energy into chemical materials, and plants are the only organisms capable of carrying out that process. Sunlight contains a certain balance of colors, including blue, red and green. So I want to know if a plant is deprived of the full spectrum, how that affects its growth