Why are Calcium and Magnesium important for soil and plant growth?

Calcium (Ca) and Magnesium (Mg) are secondary plant nutrients but are just as essential for plant growth even though those elements are required in more negligible amounts compared to macronutrients. While Calcium is part of every plant cell, it keeps cell walls upright and increases fruit set and quality.  Magnesium is a component of the chlorophyll molecule, therefore essential for photosynthesis, the mobilization of phosphorus, and plays a vital role in transporting and forming sugars and starches through the plant.   

What are deficiency symptoms?

Magnesium deficiency shows especially in the lower leaves of the plant because the plant moves all available Magnesium resources to the growing parts. Deficiency symptoms are most commonly interveinal chlorosis (veins of the leaf stay green while the rest of the tissue loses colors), leading to necrosis. Magnesium deficiency may not directly affect the plant’s fruit; however, it can reduce yield due to the plant’s stress. On the contrary to Magnesium, Calcium deficiency is first shown on the younger leaves due to its immobility. Younger leaves are smaller than usual and misshaped, show chlorotic spots, and the plant’s veins show dark veins.   

How do Calcium and Magnesium interact, and why should you measure it in your soil?

Calcium and Magnesium have similar chemical properties; both are double positively charged in the soil-water phase and on soil cation exchange sites. Levels of exchangeable Ca and Mg can vary widely in soil and may correlate closely with water-soluble Ca and Mg levels. This is highly linked to the amount of organic matter and type of clay which are both largely determine the Cation Exchange Capacity of a soil.    

Mg and Ca are not only important because of the role they play during plant growth but also because of the interaction with each other, which is a key consideration when making soil management decisions. For example, high Calcium levels can reduce the availability of Magnesium, while greater Magnesium levels can induce calcium deficiency. Even more, a reason to analyze your soil and make informed decisions when adding Ca or Mg to the soil.   

From now on AgroCares Scanner solution will allow to measure Mg and Ca right in the field.  Would you like to learn more about the new AgroCares SoilCares Manager Advanced application, contact us via