How to Make Soil Alkaline: 3 Best Ways To Raise pH

Soil can become acidic from a number of different factors. In natural ecosystems, the soil is alkaline and neutral. When soil pH levels dip below 6 or neutral, it becomes acidic. Acidic soils are harmful to the growth of plants and their ability to thrive. Fortunately, you can increase alkalinity in your soil with some simple changes in chemistry. But how to make soil alkaline? Read on to know more.

Alkaline soil is better for most garden plants because it helps balance out the acidity that comes from organic materials breaking down, or other environmental conditions such as excess rainfall or a lot of tree roots close together underground. 

What Causes Soil to Become Alkaline?

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Soil alkalinity refers to its capacity to neutralize acids by attracting them as cations (positively charged ions) by exchanging hydrogen ions with positively charged ions of strong bases such as sodium, calcium, and magnesium. The main reason for soil becoming alkaline is the use of chemical fertilizers that contain high levels of nitrogen and potassium. 

While these are essential plant nutrients, high levels of these can cause an imbalance in the soil’s pH, making it more alkaline. Another reason for soil becoming alkaline is the leaching effect of heavy rainfall. 

Rain can contain traces of salt which can then be absorbed by the soil and cause it to become more alkaline. And finally, soil can also become alkaline if there are large concentrations of carbonates in the soil, such as a result of past limestone mining activity.

How to Make Soil Alkaline?

1. Using Baking Soda

Baking soda is a naturally occurring alkaline substance that is made from sodium bicarbonate. It is often found in commercial fertilizers and can be used as a natural way to neutralize soil acidity. Bicarbonate is the main substance that gives baking soda its alkalinity and it can be used to raise the pH of the soil. To use baking soda to make alkaline soil, add it to the soil in spring or autumn.

2. Using Wood Ashes

One of the best ways to increase soil alkalinity is to use wood ashes. These are the remnants of burnt wood and are very alkaline. You can add wood ashes to your garden in several different ways. They will increase the pH of the soil if added directly to it.

Adding wood ashes to the compost will increase the alkalinity of the soil once the compost is used. They can also be used as a fertilizer by mixing them with water and applying them to the soil as a spray.

3. Composting for Alkaline Soil

Composting is a great way to naturally increase the alkalinity of your soil. The process of composting helps break down organic matter and release nutrients for plants. It also helps to balance the pH of the soil, making it more alkaline. 

Composting is a multi-step process that requires different temperatures for different stages of decomposition. During the breakdown of organic matter, the process can produce an excess of carbon dioxide that is acidic. To benefit from the alkalinity of compost, you should let it sit for at least 3 months before using it.

Liming for Alkaline Soil

If your soil is too alkaline, you can try liming to lower the pH. Liming, or the addition of lime, will reduce the alkalinity of the soil by adding a source of acid. However, it is important to note that this will only work if your soil is too alkaline. If the soil is too acidic, adding lime will not help.

Lime can be added in many different forms such as limestone, oyster shells, or agricultural limestone. The three most common limes you can use our Garden Lime, Dolomite Lime, and Hydrated Lime or Quicklime.


So, you must have understood in the article why the soil should be alkaline and how you control its pH. There are different ways to balance the pH hence, maintaining the soil quality.

Different ways to keep the soil alkaline include using compost as it breaks down the organic material which in turn makes the soil basic. But, you have to wait for some time to let it show the magic. Other ways included liming the soil, using wood ashes, baking soda, etc.

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