Effect of caffeine on plant growth
The hypothesis that mung beans watered using a coffee mixture will grow the fastest has been proven to be true.
The effect of caffeine on plant growth is still a subject under study. Using grounded coffee in garden lawns is a common practice to make plants grow faster. However, coffee also contains other ingredients like potassium and phosphorous, which are known to enhance plant growth. Experiments on plant growth using only caffeine have resulted in the plant leaves becoming wrinkled, turning brownish and exhibiting retarded growth.
Try to repeat the science fair project by using different types of seeds like corn or soy beans.
The experiment can also be repeated using pop soda or tea leaves.