Soil conditioning (also called soil neutralisation or liming) refers to the action of treating your soil for pH problems. Every soil has a pH, which can either be acid, neutral, or alkali. The majority of soils are strongly or weakly acidic, but in Ghana, many soils are very strongly acidic which causes major issues for plant growth and crop yield. For plants to grow optimally, the soil needs to be neutral. Soil conditioning is the action of neutralising your soil, with Calciprill®, Calcipower®, Aglime, or other calcium carbonate products, which usually takes place after understanding how acidic the soils are.
What Causes Soil Acidity?
Soil acidity is the major limiting factor affecting plant growth, and therefore crop yield, in Ghana. It is very important to understand it and treat it to get the best yield for crops. Many things contribute to soil acidity. Some of the causes of soil acidity:
1. Geological conditions
The underlying base rock has a huge impact on the topsoil which is the growth medium for crops. These are very often acidifying and can create very acidic soils, especially in Ghana.
2. Soil Organic Matter (SOM) contents
Soil should be a living thing. Soil Organic Matter refers to the amount of living matter in soil that could be soil flora and fauna, bacteria, fungi, and any other organic residue or matter. It is commonly referred to as humus. In natural conditions, this humus is the counterbalance to soil acidity, acting as a buffer against acidity. If SOM is low in the soil because the soil has not been effectively maintained, then the soil’s ability to neutralise itself will be limited or even totally destroyed.
The amount and type of rainfall has a big impact on soil health generally. When rainfall is very heavy, it will leach the nutrients and organic matter out of the soil. The effect of this is to take the buffer helping the soil to regulate itself away. When rainfall is very heavy and the soil cannot drain quickly enough, small rivers will form washing all the nutrients and the humus away, leaving the soil leached and denuded of nutrients and buffering ability. This is why tropical soils are often highly acidic.
4. Deforestation, slash and burn agriculture, or land preparation
When land is cleared or burnt, it removes the soil organic matter from the soil. As mentioned, the soil organic matter is the main way that soil regulates itself and stays neutral. Therefore when this is removed by burning, by deforestation, or by land preparation like ploughing and harrowing, the soil organic matter goes down and the soil becomes more acidic.
5. Application of fertilisers
When fertilisers are applied to soil, they are acidifying. This is because when the fertilisers go into the soil and come into contact with water, there is a chemical reaction. For example, when Nitrogen fertilisers are applied to the soil, the nitrogen reacts with the soil to produce nitrates, which is what the plant needs to grow. But the by-product of this chemical reaction is nitric acid, which creates more acidity.
Fertiliser Wastage: Why It is Foolish to Apply Fertiliser Until Acidity is Corrected
When soil is acid, it creates a lot of problems. Firstly, the roots of crops will have to grow in acidic conditions. A soil growing in acid conditions will never be as strong as a crop grown in neutral conditions, although some plants like pineapples and oil palm are better suited to tolerating acidic conditions than other plants like maize and cocoa, which are much more yield-limited by acidity. When you plant a seed whether it is maize, soy, groundnut, rice, cassava, or anything in the soil, it needs to be in the best environment to get the best growth.
One of the biggest problems with acidity is the conditions it creates in the soil. It affects the chemical reactions that the fertilisers have when they go into the soil and this can mean that the fertiliser applied cannot be available to the plant, in which case there is no point in spending money on fertilisers until the soil acidity is corrected. You can see on the table below just how much fertiliser is wasted the more acidic the soil becomes:
How to Correct Soil Acidity
The good news is that soil acidity is easily corrected, and this is what we mean by soil conditioning. Soil conditioning, also called neutralisation or liming, is the application of soil neutralisers in the form of Calcium Carbonate. We sell these products in Ghana as Calciprill® and CalciPOWER®. When they hit the soil, the Carbonate, which is alkali, reacts with the acid to neutralise the soil. The calcium then is free to act as a calcium fertiliser.
Demeter Ghana is the leading supplier of calcium carbonate to the Ghanaian agricultural market, supplying farmers across the country and also supplying Cocobod. Our products are specially formulated to be highly reactive as their particle size is just 2-5 microns, meaning the soil will be neutralised very quickly. Generic calcium carbonate products, with big particle sizes of up to 5mm, will not break down, sometimes for years. Our products are also organic.
Calciprill® and CalciPOWER® are best applied at land preparation stage, and will correct soil acidity within one season. They need to be applied every year that fertilisers are applied to prevent the acidifying impact of fertilisers. One of the most acidifying fertilisers is SOA, so if you are planning to use SOA as a source of Nitrogen, it is imperative you apply it in tandem with Calciprill®.
In addition to applying agricultural lime products, you should always incorporate organic matter into your soil. For example, fi you plant maize, you should always reincorporate the stover into the soil so that you can build up your soil organic matter content, which helps to regulate soil acidity.
For best results, you should get your soil tested by our team to understand how acidic your soils are.
Get in touch today to understand the acidity of your soil and get a tailor made recommendation for your soil type.
Phone: +233 24 529 7047