Macro, meso, and micro: basic elements for plant nutrition

Soil nutrients come in three basic categories: macro, meso, and micro elements.

  • Macro elements are nitrogen (N), phosphorus (P), and potassium (K). 
  • Meso elements are magnesium (Mg), calcium (Ca), and sulfur (S). 
  • Micro elements or trace elements are iron (Fe), manganese (Mn), zinc (Zn), boron (B), copper (Cu), molybdenum (Mo), and silicon (Si). 

For growth to occur there must be a proper balance between these categories. The table gives you an idea of the optimum nutrient element ratios in plant tissue.

Element Ratio in plant tissue
Molybdenunm 1
Copper 100
Manganese 1000
Calcium 100,000
Nitrogen 1,000,000