Fertilizer Experiment

Problem: Which chemical makeup of fertilizer: 10-10-10, 30-20-10, or 10-20-30 grows the tallest soybeans?

Hypothesis: I believe that the combination 10-20-30 fertilizer will grow the tallest soybeans. I believe this because soybeans do not need a lot of nitrogen, since they can get nitrogen from the atmosphere, they do not need a lot of phosphorus, since an increase in the amount of phosphorous does not increase the yield of the seed, and they need high amount of potassium, since soybeans use a lot of potassium.

Materials:
3 Soybeans
3 Pots
Soil
Fertilizer 10-10-10
Fertilizer 30-20-10
Fertilizer 10-20-30
Water
Ruler

Procedure:
1. Line up and label the three pots 1, 2, 3 respectively.
2. Fill each pot with 3 cups of soil.
3. In pot one add 1 tbsp of fertilizer 10-10-10.
4. In pot two add 1 tbsp of fertilizer 30-20-10.
5. In pot three add 1 tbsp of fertilizer 10-20-30
6. Water each pot until the soil is slightly moist – make sure that each pot gets the same amount of water.
7. Each day measure the height of the soybean and record the measurement in a chart.
8. Add water to each pot as needed – make sure that they each get the same amount
9. Repeat steps 7 and 8 for two weeks.

Conclusion: After completing the experiment, I discovered that my hypothesis was incorrect. Although the heights of all of the soybeans were similar after 2 weeks of incubation, the fertilizer with the chemical content of 10-10-10 was 1mm taller. Thus the best fertilizer for a soybean is fertilizer 10-10-10. I believe this is because the plants were in a controlled environment and the potting size was too small for the high amount of potassium concentration in the soil.