Primary Nutrients

Nitrogen (N)
Phosphorus (P)
Potassium (K)


Zinc (Zn)
Iron (Fe)
Copper (Cu)
Manganese (Mn)
Boron (B)
Molybdenum (Mo)
Chlorine (Cl)

Secondary Nutrients

Sulfur (S)
Calcium (Ca)
Magnesium (Mg)


  • Nitrogen (N), Phosphorus (P),  and Potassium (K) are the most required nutrients and are often found deficient in plants.
  • Deficiency symptoms for any element depend primarily on two factors:
    – the role of the element
    – the ease of translation from matured leaves to new leaves


  • Over fertilization or fertilization at the wrong time can have harmful effects on plant growth.
  • It is important to plan fertilizer application according to plant requirements and environmental factors and limitations

Fertilizer Types

  • Organic: natural materials with limited to no processing
  • Processed fertilizers: manufactured or extracted from natural materials often undergoes extensive processing

Reading Fertilizer Labels

Fertilizer is usually labeled with just numbers such as 5-10-10. This always refers to the amount of N, P, and K, respectively. Therefore, it contains 5% N, 10% P, and 10% K.

Soil Tests

  • Can confirm whether a nutrient or amendment needs to be applied
  • Take a representative sample by compositing 10 samples at the 0-6in depth, mix, and subsample.
  • Use stainless steel or plastic tools
  • Label and transport or ship to lab ASAP