1. Soil pH and Aeration

2. PH Plants tend to grow best in neutral or slightly acidic soil.
Plants are very sensitive to the changes in pH.
Plants tend to grow best in neutral or slightly acidic soil.
The more acidic the soil the less nutrients there are in the soil. 

3. But....
There are some exceptions, some plants such as the sundews grow in peat bogs where the soil is damp and acidic.

4. PH also affects the rate of osmosis
PH also affects the rate of osmosis. As you increase the pH the rate of reaction increases until it reaches a optimum pH and then when the pH gets above 8 the growth rate begins to decline. 

5. Aeration-Introducing air into the soil
Aeration of the soil is important for the healthy growth of plants. 
Oxygen is needed:
For plants to respire
For microorganisms to respire, as they are needed to decompose organic matter and for nitrification of the soil. 
To help plants to absorb water and nutrients
Top help prevent toxins forming in the soil
To help prevent plants from contracting disease. 

7. The effect of pH on plant growth
As the Ph of the soil increases, the taller the grass will grow. 
The independent variable is the change of the pH of the soil (1,3,5,7,9,11).
 The dependant variable is the length of the grass. We will be measuring this in centimetres.
 The control variable is the water (same amount in each plant pot and distilled water), same grass seeds, same temperature and same light intensity.

8. Equipment 6 plant pots Ruler​
30 grams of seeds (5g in each plant pot)​
Soil of different pH’s (1,3,5,7,9,11)​
Water (every 2 days- 100 ml)​
100ml beaker to measure the water

9. Results Table