Question

Gardeners understand that plants have specific pH requirements. Most plants thrive in soil with a pH that is slightly acidic, neutral, or slightly basic. 
Imagine your soil is basic, with a pH of 8.5. In soils with a high pH, minerals like iron, manganese, and phosphorus are less available to plants. How can you lower the pH to an appropriate level so your garden plants will thrive?

Answer 1

In order to lower the PH to an appropriate level so that garden plants thrive,

the gardener should add a natural acid like pine needles or humus.

To add a base like calcium carbonate or limestone. Acids have a PH which is less than 7.

 If a base is added to an acid, the PH is raised. Adding humus will decrease the PH as it is also acidic. Adding fertilizer may help the plants, but it won't change the PH neither watering will.

Answer 2

Answer:

You can lower the pH of this soil by incorporating organic matter.

Explanation:

Incorporating organic matter is the cheapest method to reduce soil pH. Lands with high organic matter content have a lower pH as well as contain large amounts of nutrients.

Organic matter was attributed to the origin of soil acidity, since its decomposition produces organic acids that would give this acid character to the soil. The acid soils would be saturated with H + and higher amount of Al³. Incorporating compost, peat would be an alternative to lowering the pH. However, keep in mind that this is not a fast process and it takes time to take effect.

Therefore, add organic matter to the highly alkaline soil (pH above 8.5), incorporating it into the arable layer. Leaves, twigs, plant residues when incorporated into the soil gradually reduce the pH. Their decomposition by soil microorganisms gives rise to acidic products. But we should expect long-term results as decomposition of plant waste takes time to alter the soil. Many prefer to apply annual amounts of organic matter to lower the pH. On the other hand, consider the benefits that this organic matter gives to the soil. Forming green manure crops should be standard practice and will help in this process of lowering the pH. Plant and incorporate the plants into the arable soil layer.