Types of fertilisers and their characteristics
Mineral fertilisers
The European mineral fertiliser industry transforms millions of tonnes of natural raw materials such as air, natural gas and mined ores into high-quality plant nutrition products.
Nitrogen fertilisers
Nitrogen-based fertilisers are the most commonly used in Europe.
The main products are nitrate-based fertilisers, such as ammonium nitrate (AN) and calcium ammonium nitrate (CAN), which are well suited to most European soils and climatic conditions.
Other nitrogen fertilisers include ammonium sulphate and ammonium sulphate nitrate, calcium nitrate, sodium nitrate, Chilean nitrate and anhydrous ammonia.
Nitrogen fertilisers with inhibitors
Certain climatic and soil conditions can lead to nitrogen immobilisation, denitrification, evaporation or leaching, reducing fertiliser efficiency. In response, the industry has developed special types of fertilisers designed to reduce these effects. These include foliar fertilisers, slow- and controlled-release fertilisers, and fertiliser additives such as urease and nitrification inhibitors.
Phosphorus fertilisers
The most common phosphorus fertilisers are single superphosphate (SSP), triple superphosphate (TSP), monoammonium phosphate (MAP), diammonium phosphate (DSP) and liquid ammonium polyphosphate.
Different fertiliser products have different release profiles and require different spreader settings for effective application.
Potassium fertilisers
Potassium is also available in a number of fertilisers that contain potassium alone or two or more nutrients and include potassium chloride (KCl), potassium sulphate (K2SO4) or potassium sulphate (SOP), potassium nitrate (KNO3), known as KN.
Calcium, magnesium and sulphur
Calcium (Ca), magnesium (Mg) and sulphur (S) are essential secondary plant nutrients. They are not usually applied as straight fertilisers, but in combination with the main nutrients N, P and K.
Sulphur is often added to straight nitrogen fertilisers, such as ammonium nitrate.
Other sources of sulphur are single superphosphate (SSP), potassium sulphate (SOP) and magnesium sulphate, the latter of which also contains magnesium.
Calcium is applied mainly in the form of calcium nitrate, gypsum (calcium sulphate) or lime/dolomite (calcium carbonate), of which calcium nitrate is the only readily available source of calcium for plants.
Micronutrient fertilisers
Today, a large number of special fertilisers are available to supply plants with important micronutrients such as iron, manganese, boron, zinc and copper. They can be either inorganic or organic compounds, with inorganic varieties further divided into water-soluble and insoluble products.
Inhibitors
Today, there are two main types of inhibitors available to EU farmers.
Nitrification inhibitors are chemical compounds that slow the nitrification of ammonium by suppressing the activity of nitrosomonas bacteria in the soil. The aim is to keep ammonium in its soil-stable form and delay its conversion into nitrate. This temporarily reduces the proportion of nitrates in the soil, and therefore the potential for leaching losses into water or formation of N2O gas in the atmosphere.
Urease inhibitors are chemical compounds that slow the first step in the breakdown of urea in soil – hydrolysis – which can lead to NH3 emissions and can occur before its conversion into ammonium. They contribute to a significant reduction in ammonia emissions into the air, one of the main air pollutants.
Organic fertilisers
Plant residues, animal manure and sludge are the main organic fertilisers. Although they have different nutritional value, they are generally found on the farm and the nutrients and organic carbon they contain are recycled. Animal manures and sludge cover a wide range of nutrient sources with different physical properties and nutrient contents. In addition, their nutrient content varies by region and depends on the type of animal and the farm management system.
Other types of plant nutrition
Different fertilising products can help farmers adapt their fertilisation practices to environmental and farm conditions: organic fertilisers, organo-mineral fertilisers, mineral fertilisers, including inhibitors, liming materials, growing media, plant biostimulants and others.
