Here at Arlington High School, we have a Climatarium in each Biology classroom. The Climatarium is capable of setting up as many as four microenvironments, each with its own light source. In addition, each half of the Climatarium can be set on a timer to control the number of hours of light. Throughout the year, we are able to implement this wonderful piece of technology into our lessons.  

Using the steps of the scientific method, the students developed an appropriate experiment to find the answer to their question. Results are below.

Hypothesis:   I think that the plants will grow better and grow more in red light and white light. I think that the plants will not grow as well in the green light.  

Materials:   In order to test my hypothesis I will need red light, green light, seeds, white light, plastic cups, plant food, water, and soil.

Methods:   To test my hypothesis I am going to poke holes in nine different plastic cups, I will fill the cups half way with soil and then put three to four seeds in. After putting the seeds in the cups, I will cover the seeds with a little soil and then water them. In a Climatarium, I will put a group of plants in red, green, and white light. I will continue watering them every other day or if the soil appears dry. I will also measure the height of the plant every other day by using a metric ruler. I will also check the color of the plant to determine the rate of photosynthesis. Also, I will measure the growth rate by measuring the height of the plant.  

What is your control for the experiment?   I am going to use white light for my control.

What is your variable for the experiment?   I am going to use red light and green light as my variable.  

Observation:   When I put my plants in the Climatarium, I was waiting to see if my plants would grow better in a different color light. The ones that I put in the red and green light died or did not grow well. The plants that I put in the white light grew well. I think the reason why the plants grew better in the white light rather then the green or red light is because the white light has all the colors in its wavelength. I watered my plants every other day or every two days. The ones that I watered every two days grew better, they were in the white light. The ones that I watered in the red and green light didn't grow well.  

Results:   The results of my plants were that most of them died when they were in the red and green light. The ones that did grow were in the white light.  

Conclusion:   I came to conclude that my hypothesis was not fully correct. In my hypothesis I said that the plants will grow better in red and white light. The plants did not grow in the red light because it only has red wavelength.  

The plants in the white light grew because they got all of the different wavelengths. Plants absorb blue and red light best, in white light.