Are Party Drink Spills Bad for Backyard Plants?

Overview

Many people throw away their unfinished drinks on plants. This project looks at how water, coffee, lemonade, tea, and soda can affect the plant growth of cherry tomatoes, Thai Chili peppers, red bell peppers, and poblano ancho peppers. These plants represent the plants that I have seen people throw away their drinks during events hosted at my house. The question I am trying to answer through this science project is: Do any of the liquids have a positive or negative impact on the plant’s growth compared to water? During the middle of my experiment, there was an infestation of aphids and worms. To get rid of them, I used the Neem Max neem oil. To make sure that all the plants were kept at the same conditions, I sprayed the neem oil on all the plants. My hypothesis is that the plants grown with water will grow the best out of all the other plants, meaning that I believe it will have the most stabilized growth and heath. Each type of plant was grown with a different type of liquid for a month. I recorded the soil humidity, the light, the soil temperature, the soil’s pH level, and plant condition everyday, and height and thickness every 2 days. In addition to that, I watered the plants with their assigned liquid when the humidity of the soil was dry. After the last recording, the results showed that coffee has the most positive effect on the plants. The coffee kept the plants healthy, with very little necrosis and chlorosis. Water also had a positive effect on the plants, keeping them healthy throughout my science project. Although it had kept the plants healthy, there was minor chlorosis and necrosis, more than the plants grown with coffee. Lemonade had a negative effect on the plants. There was severe necrosis, chlorosis, and some plant deaths. Tea kept the plants alive, but it didn’t have a complete negative or positive affect. There was some chlorosis, as well as some necrosis. Lastly, soda had a negative effect on the plants. There wasn’t much necrosis or chlorosis, but the leaves of the plants were very droopy and weak. Many leaves on the plants were lost. In conclusion, the best liquid was coffee. Although water and coffee had about the same amount of necrosis and chlorosis, based on the visual appearance, coffee was the liquid that kept the plants the healthiest.

Competition history

• CSEF 2026 Plant Biology (Junior Division) · Entry J-18-17

Related projects

Closest projects by meaning, across every fair and year in the corpus.

Browse more like this

• All Plant Sciences projects
• CSEF Plant Sciences projects
• Every CSEF 2026 project