Studying the effectiveness of different fertilizers in the classroom offers the opportunity to discuss why farmers use certain fertilizers and the impact on the planet. Students test the fertilizers by planting grass seeds in pots and sprinkling different samples with different fertilizers, then monitoring the growth while keeping all the other factors constant. The experiments can determine the effectiveness of organic versus inorganic fertilizers, or test the growth-enhancing qualities of different fertilizer brands or compounds. More complex university-level studies evaluate the long-term effectiveness and potential harmful results of various products.
Science experiments can test the growth rates and the quantity of vegetable matter produced by various types of grasses and evaluate the potential of a certain grass as a biofuel. These experiments vary from simple high school experiments that study growth rates of different grasses in pots over a matter of weeks to university-level studies that study a variety of factors over much longer lengths of time using acres of land instead of pots. For example, a University of Wisconsin study of the comparative value of switchgrass versus coal took two years to complete.
Students can also test various types of growing mediums using pots and grass seeds. Different types of soils with various amounts of clay, silt, gravel and sand can be evaluated. Each sample is watered at precisely the same rate, and results are measured over a period of time. Students can also test how adding one ingredient to a soil mixture affects the growth. Experiments can also determine the medium's capacity to hold water over time.
Students can study how light affects growth rate of different grasses in various mediums. The students place their grass pots different distances away from different light sources such as sunlight through a window, fluorescent lighting, incandescent lighting or lighting from other bulbs like tungsten. All the grass pots are watered and fertilized at the same rate, with the only variant being the light source. Students can also test the effectiveness of a light source based on its color.