Plant biology projects are accessible, hands-on ways for students to explore scientific research methods. Students who are already curious about natural ecosystems, climate science, soil science, and/or agriculture can use plant-focused science fair projects to fuel structured intellectual growth. Below, we’ll discuss a few of the many reasons you should consider a plant science fair project this year. We’ll then provide inspiration for specific project ideas, go over strong experimental design principles, and offer tips to help your project stand out on presentation day.
Why Choose Plant-Based Science Projects
Plant science fair projects are excellent choices for many reasons. First, they’re relatively easy to set up and observe relative to other subject areas. They also lead to clear, measurable outcomes with immediate real-world relevance for food production and/or ecology. Furthermore, plant-based projects are open to students of all levels. All students with patience, independence, and careful observation skills can apply and strengthen those abilities through plant biology projects.
Plant Growing Science Fair Project Ideas
The Effects of Light on Plant Growth
In this project, you’ll observe photosynthesis in action! The experimental design is fairly straightforward but still leaves plenty of room for you to customize the project.
Here’s one possible research question: Does longer light exposure correlate to taller plant growth over time in [chosen species]? In this project, you’ll expose plants to 3, 6, 9, or 12 hours of light per day.
Another research question could be: Which type of light exposure is most effective for plant growth over time in [chosen species]? In this version, you would compare the types of light received from:
Sunlight
Simulated full-spectrum grow lights
LED bulbs
Fluorescent bulbs
Once you’ve identified your research question, you’ll need to establish a hypothesis. Using your knowledge of biological concepts, what do you predict the data will show? Will there be an observable trend between the variables? What concepts lead you to those predictions?
Next, you’ll acquire seeds for the type of plant you want to study. To minimize genetic differences, they should all be from the same species, variety, and source. A common choice for science fair projects is Brassica rapa, also called “Wisconsin Fast Plants”, because of their fast life cycle.
You’ll then design an experimental procedure that varies the light exposure that each group of individual plants receives. All other variables (such as watering amount and soil type) should remain constant across the specimens. Then, you’ll germinate and plant your seeds and conduct the experiment.
Over the course of the study, record all of the details of your materials and methods (e.g. dimensions of the spaces, watering schedules, etc.) in your lab notebook.
Finally, you’ll measure the heights of the plants from the soil every seven days over the course of 4-6 weeks. Be sure to measure them at the same time every day! You’ll then compare the results. You should have several individual plants for each group of the experiment. That way, you can calculate and compare the averages, which can be visualized in a bar graph or other chart.
The Effects of Soil Additives on Plant Health
This is another fascinating project for students who are excited to explore plant biology. In this one, you’ll learn about plant growth by experimenting with materials added to soils.
This project is inspired by Ava Zhang’s ISEF prize-winning project, Soilization of Sand. Ava hypothesized that plant health could be improved for soybeans in agricultural environments with sandy soil by adding two key, low-cost resources: Bentonite and either lichen or mycorrhizal fungus. Her abstract, methods, and conclusions (linked above) are definitely worth a read!
Building on this project, you’ll study the effects of these or other additives on another crop species in sandy soil. Instead of studying soybeans, you could study:
Peas
Radishes
Tomatoes
Carrots
Lettuce
Wheat
For the purposes of this project, you’ll pick up to three additives and one plant to study. Your research question could be a version of: What is the most efficient combination of additives for increasing overall plant health and photosynthesis in [chosen species]? Similar to the project described above, you’ll first write down your hypothesis and the reasoning behind it. For example, you might consider previous studies on the additives, or existing knowledge about how well your chosen plant has been able to grow in different conditions.
After designing your methods, you’ll plant the germinated uniform seeds in your chosen soil with varied concentrations of the additives, or no additive at all (control). Aim to keep light exposure (and other variables) as consistent as possible from plant to plant.
Furthermore, in addition to measuring the height of each plant, you’ll use a smartphone app to measure the Dark Green Color Index (DGCI), count the number of leaves, and take notes on overall apparent health.
For more plant project inspiration, try out the Polygence Project Idea Generator!
Designing a Strong Experiment
As shown in the project ideas above, strong experimental designs are clearly scoped and structured. Before designing your own experiment, it’s best to read the methods outlined by previous studies within your topic. Try to identify their strong and weak points.
One of the first steps in experimental design is to clearly define independent and dependent variables. For instance, if your independent variable is the type of light source, then your dependent variable (what you measure) could be the height of the plant. Articulating a hypothesis will give you something to compare your results with at the end of the experiment: was your hypothesis correct? Why or why not? Finally, plant scientists must be consistent and highly methodical in how they collect and analyze data. This ensures reliable results at every stage.
Analyzing and Presenting Results
Data analysis and presentation takes place after the experiments are fully completed. The overall goal is to understand any patterns that your experiment revealed, and then to communicate them to your audience. This is done by comparing data across groups to draw evidence-based conclusions. For example, you could turn your results into a graph or chart accompanied by an explanation of the scientific significance of your work. Finally, for most science fairs, you’ll be required to present your work to judges (usually a panel of science teachers). It’s important to give a clear and concise overview of the project. Be prepared to respond thoughtfully to any questions they may have, as well!
Making Your Project Stand Out
Plant projects that excel at science fairs tend to be innovative and closely connected to real-world issues. For example, many of the abstracts for ISEF-winning plant-focused projects open by presenting the real-world ecological, environmental, or agricultural significance of the project. For example:
“To address the depletion of seagrass…” (Thermal Tolerance in Seagrass)
“Due to the global demand for CO2 removal mechanisms…” (Enhancing Photosynthesis via RUBY Plasmid Delivery)
Finally, according to the ISEF judging criteria, the presentation itself accounts for 35% of the overall score. Judges appreciate clear and well-structured displays that reflect not just on the project’s significance, but also on its limitations. (For instance: how could your project be expanded on in the future?)
How Guided Support Enhances Projects
There are many benefits of working with a mentor, and structured support from research mentors can help take students’ independent science fair projects to the next level. For example, mentors can connect students to valuable resources such as previously published studies. They can also offer advice on experimental designs and answer methodology questions for ensuring reliable data collection. Finally, they can even help students strengthen their final presentations by providing personalized feedback on charts and graphics, and by conducting mock interviews so that students can practice answering questions from expert judges.
Conclusion
For your next science fair project, turn plant growth into intellectual growth! Plant growing projects can be easy to set up, are very hands-on, and have clear impacts on real-world issues.
Polygence’s Research Mentorship Program connects students with experienced research mentors. This personalized and guided support is designed to help you build key skills for strong results in independent projects. We also offer Polygence Pods — 6-week courses for students seeking a lower-commitment option. Pods topics range from environmental sustainability to data analysis methods for research. Alternatively, for more industry-oriented students, Work Lab places students within cutting-edge startup companies. There, they receive dedicated training and work alongside founders on real world problems.
Hear from our students about all the ways Polygence can help your project take root and branch out!