Essential Plant Nutrients: Secondary and Trace Elements

Secondary and Trace Elements in Soil

Secondary elements are nutrients that abound in the soil and are consumed in large quantities by plants. This group includes Calcium, Magnesium, and Sulfur. Micronutrients are elements that plants consume in smaller amounts, yet they remain essential for healthy development. These include Iron, Manganese, Zinc, Copper, Molybdenum, Boron, and Chlorine.

These elements are typically present in the soil in sufficient quantities to meet plant needs. Therefore, fertilizers like Nitrophoska are generally sufficient, except under the following conditions:

• Soil depletion: Caused by high crop yields.
• Chemical fertilizers: Synthetic fertilizers often lack the organic matter required to replenish these elements.
• Fertilizer purity: High-purity fertilizers often lack the specific secondary and trace elements found in natural sources.

When applying supplemental nutrients, exercise caution, as the threshold between deficiency and toxicity is very narrow. The most toxic elements include copper, boron, molybdenum, and manganese.

Secondary Elements

• Calcium: Nourishes the plant and becomes part of the cellular complex. It is involved in root growth, improves soil quality by decreasing acidity, accelerates organic decomposition, enhances soil structure, and promotes nutrient retention.
• Magnesium: A vital component of chlorophyll; its deficiency causes yellowing of the leaves.
• Sulfur: Deficiencies are detected when young leaves turn a yellowish-green color along the veins. It is often included in common fertilizers.

Trace Elements

• Iron: Essential for chlorophyll formation; deficiency causes yellowing between the leaf veins.
• Manganese: Deficiency manifests as a reddish-yellow color between leaf veins, while the veins themselves remain green.
• Zinc: Essential for plant growth; scarcity significantly slows development.
• Copper: Excess is highly toxic to plants, though deficiencies are difficult to detect visually.
• Molybdenum: Deficiency causes plants to appear yellowish, similar to nitrogen deficiency.
• Boron: Shortage causes young leaves to stop growing and dry out; the terminal bud may also dry, resulting in a rosette appearance.
• Chlorine: Deficiencies are rarely observed.