Calcium Fertilizer:
Calcium is a secondary element required by plants. It is generally incorporated into cell walls in the form of pectin calcium, influencing the growth of root and stem tips, promoting fruit formation, and preventing fruit cracking and softness.
Calcium is a highly mobile element, primarily found in stems and leaves, with more in older leaves than younger leaves and less in fruit than leaves. Calcium can only be transported in one direction (upward). Mineral elements are generally transported within plants through the phloem and xylem, but calcium is almost exclusively transported through the xylem, primarily through transpiration, transporting it upwards from the bottom up.
Symptoms of Calcium Deficiency:
Calcium deficiency in crops generally manifests first in new leaves, as calcium is easily fixed within the plant. Once fixed, it becomes non-mobile.
a. Calcium deficiency can inhibit the growth of root tips, stems, and leaves, resulting in small, dull, dark green leaves and curled young leaves.
b. Calcium deficiency can lead to poor fruit development, impaired sugar accumulation, and the development of soft and cracked fruit.
c. Calcium deficiency can affect crop yields, such as heartburn in Chinese cabbage, premature aging in winter melon, and bitter pit in apples.
d. Calcium deficiency can weaken crops’ resistance to cold and drought, making them more susceptible to lodging and pests and diseases.
Common calcium fertilizers: Differences between amino acid calcium, sugar alcohol calcium, EDTA calcium, fulvic acid calcium, and ammonium nitrate calcium
Amino acid calcium:
Amino acid calcium is a highly effective calcium fertilizer using amino acids as a carrier. When crops absorb amino acids, they also promote the absorption and utilization of calcium fertilizer. Amino acids themselves are nutrients that promote enzyme metabolism and protein synthesis, increasing the sugar content of fruits. Therefore, compounded amino acid calcium is more effective and has a higher absorption and utilization rate. Of the more than 20 amino acids, only aspartic acid and glutamic acid can chelate calcium.
Sugar alcohol calcium:
Calcium fertilizer is chelated using xylitol, mannitol, and other ingredients in a suitable proportion. Sugar alcohols are primary products of photosynthesis and are recognized by crops as their own substances, facilitating the transport and absorption of calcium fertilizers. They are a highly mobile calcium fertilizer that can be transported up and down the soil.
Calcium EDTA offers excellent solubility, compatibility, and leaf absorption, making it the most efficient calcium fertilizer. However, its calcium content is only approximately 10%, and its price is high. It is difficult to degrade and can easily cause heavy metal contamination.
Calcium Fulvic Acid:
Fulvic acid is a key component of soil organic matter. It can steadily and continuously release calcium ions with a long-lasting, slow release rate, and is soil- and environmentally friendly. Weakly alkaline solutions facilitate the dissolution of calcium fulvic acid, while acidic soils or solutions hinder its absorption.
Calcium Ammonium Nitrate:
It is water-soluble, affordable, and easy to use. It supplements both calcium and nitrogen, and its effects are rapid upon spraying. However, it is easily adsorbed and fixed by soil colloids and reacts with phosphate and carbonate ions to form precipitates. Acidic soils are not conducive to calcium absorption; neutral or slightly alkaline soils are more conducive to calcium absorption.
Many people are also interested in “fluid calcium.” Fluid calcium actually includes various chelated liquid calcium fertilizers such as amino acid calcium and sugar alcohol calcium. “Fluoride” is just a conceptual term, symbolically indicating that this type of calcium fertilizer has a high absorption and utilization rate. Calcium magnesium phosphate fertilizers can also supplement calcium, but they are generally classified as citrate-soluble phosphate fertilizers.
