What is NPK labeled in the fertilizer?

Firstly, fertilizer is any organic or inorganic material of natural or synthetic origin (other than liming materials) that is added to a soil to supply one or more plant nutrients essential to the growth of plants.


Fertilizers typically provide, in varying proportions:

• 6 Macronutrients: nitrogen (N), phosphorus (P), potassium (K), calcium (Ca), magnesium (Mg), and sulfur (S)
• 8 Micronutrients: boron (B), chlorine (Cl), copper (Cu), iron (Fe), manganese (Mn), molybdenum (Mo), zinc (Zn) and nickel (Ni)

Only three other macronutrients are required by all plants: carbon, hydrogen, and oxygen. These nutrients are supplied by water (through rainfall or irrigation) and carbon dioxide in the atmosphere.

NPK rating (or N-P-K) is used to label fertilizer based on the relative content of the chemical elements nitrogen (N), phosphorus (P), and potassium (K) that are commonly used in fertilizers. The N value is the percentage of elemental nitrogen by weight in the fertilizer. The values for P and K represent the amount of oxide in the form of P₂O₅ and K₂O that would be present in the fertilizer if all the elemental phosphorus and potassium were oxidized into these forms.

The three elements promote plant growth in three different ways. In simple terms, these are:

• N – nitrogen: promotes the growth of leaves and vegetation
• P – phosphorus: promotes root and shoot growth
• K – potassium: promotes flowering and fruiting

*An easier way to remember what's NPK for~ Or just rmb KNP~ :)