The Effectiveness of Recycled Material as a Hydroponic Rooting Medium Materials and Methods Results Discussion and Conclusion Introduction Lauren Godfrey, Sara Orbe, Gianna Petillo and Adara Temizler -- Colonia Middle School Plastic waste is destroying our environment by polluting water and every year it costs billions of dollars to clean up. “Some 10 million to 20 million tons of plastic enter the oceans every year, accounting for up to 80 percent of the trash at sea and on shores” (Ocean Plastic Pollution Costs $13 Billion a Year, and Your Face Scrub Is Part of the Problem). By replacing the sponges or other growing mediums in hydroponic kits with used plastic onion sacks, we can help eliminate the amount of plastic in the oceans by recycling them as plant medium used in hydroponics. Hydroponics allows farmers and plant to easily grow plants indoors with just water and plant nutrients. Growing plants indoors prevents cold weather from causing the plants to die. Although the idea of hydroponics is still new to some or is extremely expensive at the moment, the article Living Green states that hydroponics is beneficial because it is “Eco-friendly” and because of its “portability.” Hydroponics is also extremely environmentally friendly for farmers because as “Hydroponics accomplishes one of the main goals set out by organic farmers… to not use any amount of soil so erosion can be eradicated” (Outdoor Hydro). Recycling plastic waste is also important in our community because we can save animals from being suffocated by plastic floating in water Therefore, by using old onion sacks as a growing medium, we reuse plastics, can grow plants, and saving the environment. Hypothesis After 25 days of growth, the experimental calendula flowers had an average of 1.5 leaves. The control calendula flowers had an average 2.8 leaves. After 25 days of growth, the tallest experimental calendula stem was 2.2 centimeters. The tallest control calendula stem was 2.7 centimeters. For charts refer to Figures 10 and 11. Our data refutes the hypothesis because the experimental Calendula plants did not grow faster than the control Calendula plants. This could be because the experimental Calendula flowers were not always as moist as the control flowers. The control seeds were constantly being moistened by the hydroponic sponge, but the experimental seeds were in a plastic onion sac which could not moisture retain. Once the experimental plants roots grew, they were able to reach the water stored in the Aerogarden, they did not reach the water fast enough. The control plants were already starting to sprout leaves at this point. Also, the placement of the experimental seeds could have affected our results. If the experimental seeds were placed closer to the water spouts, then the experimental seeds would have been more moist and have a better opportunity to grow faster. Figure 1: (Left) Experimental pod created by cutting onion sacks and placing it on the regular hydroponic pod. (Right) A regular hydroponic pod. Our hypothesis was if we used onion sacks as a growing medium in a hydroponic system, then flowers will grow faster compared to plants grown in a sponge medium commonly used in hydroponic systems. Figure 2: One Calendula seed was put into the sponge of each control pod. Figure 3: One Calendula seed was placed in the onion sack of each experimental pod. Figure 4: The Aerogardens with seed filled pods. The control group is on the right and the experimental group is on the left. Figure 5: The experimental Aerogarden. Figure 6: The control Aerogarden. Figure 7: Plant nutrients. Figure 8: Growth of control plant. Figure 9: Growth after 28 days. Our hypothesis was that if we used onion sacks as a growing medium in hydroponics, the plants would grow quicker than the regular sponge medium provided with the kit. If we wanted to retest or further our hypothesis, we would use a different plant growing medium since our hypothesis was not supported. Overall the data was extremely useful by showing why recycling and reusing plastic is important to the community. Our data also showed that even though the seeds in the onion sacks did not grow, there are different plant mediums that can be used such as plastic bags or bottles. One change we could have made to our experimental design would be to grow the plants for a longer amount of time. Because we had limited time, we did not have time to see whether the variable or constant would have grown faster. Also, we could have used a different material than onion sacks because the holes were a bit big for the seeds and when we tried to fold over the plastic to make the holes smaller, it made it slightly difficult for the roots to grow through(Figures 1 and 3). Using more seeds in each pod in case one fell out of the growing medium could have changed the results. The materials our group used were a q-tip, a ruler, plant nutrients, water, a spray bottle, 2 AeroGardens, 6 hydroponic sponges, 12 hydroponic pods, 6 onion sack strips, one weight, one siphon, one cut out plexi glass, one measuring cup and 12 Calendula seeds. The first step to conducting our experiment was creating the experimental hydroponic pods with the onion sacks. (Figure 1) We covered each of the six experimental pods with onion sacks and rubber bands. We then put each of the seeds in the original hydroponic pods and the new experimental ones. (Figures 2 and 3) The pods were placed in their correct spots in the Aerogardens which was eventually set up. (Figure 4) Both the experimental Aerogarden and the control Aerogarden were monitored daily. (Figures 5 and 6) After two weeks, the Aerogardens were refilled with water and 8mL of plant nutrients.(Figure 7) We recorded the height of the tallest stem in each Aerogarden and how many leaves were on each Calendula flower. (Figures 10 and 11)