NPK Fertiliser

NPK fertilisers, also known as complete fertilisers, contain the three most important plant nutrients – nitrogen (N), phosphorus (P) and potassium (K) – in varying ratios. This combination covers the basic nutrient requirements of many crop plants.

In addition to these primary nutrients, NPK fertilisers may also contain what are known as secondary nutrients, including sulphur, calcium and magnesium. Trace elements such as iron, manganese or boron are often included too, or can be supplied separately as dedicated trace element fertilisers if needed.

In simple terms, the roles of the most important nutrients can be explained as follows:

• Nitrogen (N) promotes the growth of leaves and green plant parts
• Phosphorus (P) supports root development as well as flower and fruit formation
• Potassium (K) strengthens plant structure, stability and resistance
• Magnesium (Mg) is a key component of chlorophyll and supports nutrient uptake

The NPK ratio stated on the packaging indicates the proportions of the primary nutrients it contains. Depending on the plant species, soil conditions and growth stage, a suitable NPK fertiliser should be chosen to avoid over- or under-supply.