HORTICULTURE

Detailed explanation-1: -It has been determined that most plant nutrients are optimally available to plants within this 6.5 to 7.5 pH range, plus this range of pH is generally very compatible to plant root growth.

Detailed explanation-2: -The pH range 5.5–6.5 is optimal for plant growth as the availability of nutrients is optimal.

Detailed explanation-3: -Most nutrients that plants need can dissolve easily when the pH of the soil solution ranges from 6.0 to 7.5. Below pH 6.0, some nutrients, such as nitrogen, phosphorus, and potassium, are less available.

Detailed explanation-4: -At a higher pH, soil builds up toxic levels of certain nutrients. For example, molybdenum, typically a plant nutrient, becomes poisonous to plants in large amounts. Molybdenum soil levels increase in a high pH environment. Introducing a plant food that results in high pH levels can be toxic to that plant.