
Companion Planting with Tomato, Corn, and Onion
Easy
Can planting two species in the same pot help or hurt their growth? You set up five pots: tomato alone, onion alone, corn alone, tomato with onion, and tomato with corn. Each pot holds three plants.
After 10 days, you measure the average height of each group. Tomato plants paired with onions grow taller than tomatoes grown alone. Tomatoes paired with corn grow shorter than either plant on its own.
The results show that some plant combinations boost growth while others slow it down.
Hypothesis
The hypothesis is that some plants will interact well with one another and increase in their rate of growth whereas other plants may not get along well together and growth will be delayed.
Science Concepts Learned
Companion Planting
Some plants grow better when planted next to certain neighbors — a principle called companion planting. In this experiment, tomato plants paired with onions grew taller than tomatoes grown alone, while tomatoes paired with corn grew shorter than either plant on its own. These results show that some plant combinations boost growth while others slow it down, depending on how well the species interact.
Method & Materials
You will plant different types of plants in 5 pots, measure the growth rate of the plants, and calculate the average height.
You will need 1 packet of tomato seeds, 1 packet of corn seeds, 6 onions, 5 plastic pots, enough soil to fill the 5 pots, and a ruler.
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See what’s includedResults
The experiment showed that tomato plants grow well with onions but not with corn. The tomato plant grew an average of 48mm by itself in pot A but was able to grow up to 65mm when planted with the onion in pot D. However the tomato planted in pot E together with the corn, was only able to grow 28mm in the 10 days.
Why do this project?
This science project is interesting because it explores the idea of companion planting and how it can help reduce the use of chemical pesticides to protect the plants.
Also Consider
To further explore this project, consider repeating the experiment using different plants like radish, potato and peas. Also, consider continuing the experiment over a longer period.
Full project details
Additional information and source material for this project are available below.Related video
These videos explain the science behind this project and demonstrate key concepts used in the experiment.
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