Soil pH Investigation

Purpose: To compare plant growth in different pH level soil

Hypothesis: I think that bean plants will grow better in acid soils because beans plants are acidifying foods.

Materials:

• 4 plastic labeled water bottles

• 4 white Styrofoam cups

• 8 bean seeds

• Soil
  

Solutions

• pH4-1.5 teaspoons of vinegar in 500 ml of water
• pH6-0.5 teaspoons of vinegar in 500 ml of water
• pH7-tap water
• pH 9-one teaspoon of baking soda in 500 ml of water

Procedure:

1. Two beans were planted in each of the four cups.
2. Each solution was made and stored in individual bottles to indicate which.
3. The plants were watered with tap water everyday until it reaches 1cm in height.
4. Each plant was watered with different solutions once it reached 1cm in height.
5. Recorded observations into chart every other day.

Observations:

I planted all four plants and watered each of them everyday but only 2 grew, while the other 2 started growing mold in the soil. A week later one plant died, turned brown and shriveled up So I ended up with one left.

Conclusion:
My hypothesis was incorrect based on the data chart given.
The plant with the pH level of 7 which was normal tap water grew much larger than the acid watered plant. The plant with the highest acid level(pH of 4), was the shortest of the rest. I noticed from the chart that plants grow larger when it has pH levels in between base and acid. The plants that were watered with high or low pH levels solution grew much shorter. Despite all, regular tap water was the best substance to water plants with.