Sure, compost is made from kitchen scraps ranging from broccoli stems to coffee grounds, but the term is usually applied to plant material once microbes have heated, then transformed it into a rich, earthy mixture. Eighth grade student Aaron Didich had another idea.
Concerned about the quantity of food scraps that go to waste in landfills, Aaron wondered whether he could design a way to recycle food scraps quickly. Then he spied his mother's blender. (A company later donated a heavy-duty juicer after he wrote them about his proposed experiment!) Using water, coffee grounds, lettuce, spaghetti, and other kitchen scraps, Aaron created a juicy mixture and dubbed it "cool compost."
As part of a school science project, this young scientist set up an experiment to compare how his cool compost solution and a commercial fertilizer would affect bean plants. He carefully treated two experimental plants and a control plant with the same amount of appropriate solution once each week, then tracked plant growth and development. "The plants treated with cool compost did better than the others," he reports via e-mail. "They showed a 65 percent increase in weight in 10 weeks. And though they weren't as tall as the others, they were stockier, had more blooms, and kept blooming long after the others were through," he adds.
But Aaron's inquiry didn't end there. This past summer he planned to use his method in an outside garden, testing the soil to examine whether the compost really makes more nutrients available to plants. "I may even ask my family to do a taste test to see if there's a difference in flavor or texture in plant foods fertilized with my cool compost," he notes.
We were so intrigued by our e-mail conversation with Aaron that we wanted to share his story with the hope that it might inspire other classroom scientists. We are certainly impressed with his creative thinking, careful data gathering, and impulse to set up more investigations to further explore his question. His results surprised us, because we assumed it would take longer for nutrients to be broken down by microbes and made available to plants. Some of our questions are Why did plants seem to respond well to the cool compost? What other factors might have affected his experiment? Would other students get similar results if they were to repeat it? Consider sharing Aaron's story with your students and let us know what questions and new investigations it prompts!