NPK - what is it?

The NPK value indicates the percentage by weight of the three basic nutrient components for a plant.

The NPK value specifies the weight percentage of the three basic nutrient components that a plant should have available for optimal growth and development:

• N denotes nitrogen, which is absolutely indispensable for the growth of plants.
• P denotes phosphorus, which supports root formation, bud development and flowering.
• K denotes potassium, which provides plant strength, improves its resistance and protects the plant from possible infections.

Fertilizers containing the N-P-K elements are the basic nutrition for plants.

What is the composition of an NPK fertilizer and how do you interpret the specific values that a particular NPK fertilizer displays?

If the NPK value is 6-8-6, the plant nutrition includes 6% nitrogen, 8% phosphorus and 6% potassium (weight percentages).

NPK fertilizers containing the basic elements for healthy growth of plants are often referred to as so-called complete fertilizers. You will also often encounter the term triple fertilizers.

A fertilizer containing only phosphorus and potassium - a two-part fertilizer, also known as a PK fertilizer - is a mineral supplement for an extensive root system of plants and another effect of its use is often the production of lush flowers.

Growers also widely use single-component fertilizers containing only one of the three most important NPK elements. A single-component fertilizer gives plants an extra dose of nitrogen, phosphorus or potassium. The number for each type of fertilizer again expresses the weight percentage.

Fertilizer with NPK content and its use in practice:

• Consumption of nitrogen, phosphorus and potassium is significant for most plants, and so single-, two- and three-component fertilizers with varying NPK contents are intensively used when cultivating plants in indoor conditions during the cultivation cycle.
• Basic soil fertilization at the beginning of vegetation is important again in cases where you repeatedly use the same growing area in an outdoor environment with a smaller growing area (garden bed, plot, etc.), for example for growing fruit or vegetables. Repeated cultivation on the same area results in reduced soil fertility as nutrients are gradually depleted. Therefore it is important to add them back into the soil, which is exactly what a complete fertilizer is for.