- Mineral fertilizers, natural or chemical fertilizers?
- Single, binary or ternary mineral fertilizers
- The benefits of chemical mineral fertilizers
- The disadvantages of chemical mineral fertilizers
In the fertilizer family, organic fertilizers and mineral fertilizers are often opposed. And often the latter have bad press, being accused of polluting the soil and water. But mineral fertilizers also have their advantages. It would be a shame to stigmatize them and neglect them completely.
Mineral fertilizers, natural or chemical fertilizers?
Originally the two main mineral fertilizers, phosphorus (P) and potassium (K) came from the exploitation of natural deposits of phosphate and potash. Today, they are most often from the chemical industry.
The third thief of the NPK trio, nitrogen (N) comes from the synthesis of ammonia from the nitrogen of the air. It's a process that consumes energy.
Nitrogen, phosphorus and potassium are rarely brought as such but in forms more easily assimilated by plants: Nitrate, ammonium nitrate or urea for nitrogen - Calcium or ammonium phosphate for phosphate - Potassium chloride, nitrate or sulphate for potassium.
But you can still find natural mineral fertilizers using crushed rocks. Basalt powder is rich in silica and will provide potassium, calcium and magnesium. Mica is rich in potassium. Patentkali rich in potassium, magnesium and sulfur is very soluble and will have a fast action.
Single, binary or ternary mineral fertilizers
Simple fertilizers contain only 1 chemical element, N, P or K.
When they have multiple elements, they are called complex fertilizers.
When you buy mineral fertilizers, the bags or boxes indicate the percentage of each fertilizer element. The initials NPK are followed by 3 digits indicating the exact composition. For example NKP 16-5-5 indicates a fertilizer containing 16% nitrogen (N), 5% phosphorus (P) and 5% potassium (K). The minimum contents are guaranteed (Standards NFU 42001 to 42004).
Fertilizers also contain other nutrients necessary for the growth of plants: calcium, magnesium, sulfur, iron, manganese, zinc, copper, boron, molybdenum, chlorine.
The benefits of chemical mineral fertilizers
Mineral fertilizers act faster than organic fertilizers. They are more easily assimilated by plants. In recent decades, they have made their mark in intensive farming because of their low cost and efficiency.
In the pleasure garden or kitchen garden, they are widely present because of their qualities:
- Improved yields.
- Low cost
- Speed of action
- Ease of use.
The disadvantages of chemical mineral fertilizers
The particularly intensive use of mineral fertilizers entails risks for plants and soil quality.
- Fast fertilizer use depleted the earth: The micro-organisms of the soil being no longer solicited, they disappear. The earth becomes sterile. But now you can find "late" mineral fertilizers with a coating that allows more gradual diffusion of nutrients.
- Excess fertilizer that the plants do not use will join the water tables or the rivers. This pollution causes the eutrophication of water and we find these fertilizers into the tap water. Whatever the type of fertilization you use, it is important to make sure to use the fertilizer in the garden.
Natural mineral fertilizers have significantly fewer disadvantages. A by the patentkali which acts very quickly, the other crushed rocks have a mode of action much slower. As a result, they are mostly used in amendments.