Essential Plant Nutrients

Much has been researched and written about essential plant nutrients. Scientists have deemed that there are 20 mineral elements deemed to be essential for plant growth.

Plants get all their nutrition from minerals. They absorb these minerals as ions, dissolved in water and they are absorbed primarily via the plant roots.

A point to consider when thinking about plant nutrition is the is the application of Liebig’s law of the minimum. Baron Justus von Liebig, a German scientist in the mid 19th century, popularised the “law of the minimum,” which states that “plants will use essential elements only in proportion to each other, and the element that is in shortest supply—in proportion to the rest—will determine how well the plant uses the other nutrient elements.”

The law essentially states that a plant’s growth is limited by the lowest level of every essential element.

In other words, high levels of nutrients are wasted when any essential element is missing or supplied at a proportionately lower level. Lacking any essential mineral, no matter how seemingly insignificant, will affect the overall growth and health of the plant.

The 20 essential plant nutrients can be classified into the following 2 categories:

1. Macronutrients are used in large quantities by the plant.

  1. Structural nutrients.
  2. Primary nutrients.
  3. Secondary nutrients.

2. Micronutrients: used in small quantities by the plant.

Essential Plant Nutrients, Bio Leaf Plant Nutrients, New Zealand


1. Macronutrients:

a. Structural nutrients are utilised within the physical structure of a plant, namely:

  • Carbon (C).
  • Hydrogen (H).
  • Oxygen (O). 

These elements are obtained from the air (CO2) and water (H2O).

They form the building blocks for carbohydrates such as sugars and starch, which provide the strength of cell walls, stems, and leaves, and are also sources of energy for the plant and organisms that consume the plant.

b. Primary Nutrients:

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

These elements contribute to plant nutrient content, function of plant enzymes and biochemical processes, and integrity of plant cells. Deficiency of these nutrients contributes to reduced plant growth, health, and yield; thus they are the three most important nutrients supplied by fertilisers.

c. Secondary Nutrients:


2. Micronutrients:

The final essential elements are used in small quantities by the plant, but nevertheless are necessary for plant survival.

  • Boron (B).
  • Chlorine (Cl).
  • Copper (Cu).
  • Iron (Fe).
  • Manganese (Mn).
  • Sodium (Na).
  • Zinc (Zn).
  • Molybdenum (Mo).
  • Nickel (Ni).

Studies have also shown that a number of other mineral elements are beneficial to the growth of plants and are required for some plants and these include:

  • Silicon (Si).
  • Cobalt (Co).


The above list of nutrients is known as the essential list of elements and represents the most important nutrients required for plant growth and health. In reality, there are many other nutrients used by plants and the law of the minimum applies to them as well. Deficiencies in these elements will also affect plant growth and health.

Leave the Essential Plant Nutrients Page and take me back to the Articles Page

/* Active Campaign Vistor Tracking */