Fertilizer, natural or artificial substance containing the chemical elements that improve growth and productiveness of plants. Fertilizers enhance the natural fertility of the soil or replace the chemical elements taken from the soil by previous crops.
The use of manure and composts as fertilizers is probably almost as old as agriculture. Modern chemical fertilizers include one or more of the three elements that are most important in plant nutrition: nitrogen, phosphorus, and potassium. Of secondary importance are the elements sulfur, magnesium, and calcium.
The fertilizers has three groups;
- Straight fertilizers – supplies single nutrient Ex: Urea, Muriate of Potash
- Complex fertilizers – supplies two or more nutrient Ex: 17:17:17 NPK complex
- Mixed fertilizers- supplies two or more nutrient Ex: Groundnut mixture
Straight fertilizer can be used straight to the crops but the nutrients that have been supply are incomplete. This fertilizer usually mixed with other types of fertilizer to formulate mixed fertilizer and compound fertilizer. The advantage of this straight fertilizer is because of the low price compare to the other fertilizer. But, the effect to the crops is not good enough.
Again, as the name implies, this type of fertilizer is rich in nitrogen content. Nitrogen gets converted into ammonia when the fertilizer is applied and dissolves when rain or irrigation systems wet the ground. The nutrients from the chemical nitrogenous fertilizer are then carried through the ground into the root system of the plant. Chemical nitrogenous fertilizers usually come in the form of white granules or pellets which are used to fertilize the soil before or during planting.
Phosphate fertilizer is good for acidic soils. Obtain organic phosphates or synthetic phosphate fertilizer depending on your needs. Bone meal is usually used to make organic phosphate fertilizer by grinding or steaming. Superphosphate is the chemical version of phosphate fertilizer. It comes in three grades: single, triple and dicalcium, and it is usually used during the sowing season.
Potassium fertilizers work well in sandy soil to improve the quality of plants and vegetables by increasing the potassium content in inadequate fields. The two main varieties of potassium fertilizer are: 1) sulfate of potash and 2) muriate of potash. Sulfate of potash is made by treating potassium chloride with magnesium sulfate to produce a fertilizer that can be used to enrich garden soil any time up to sowing. Muriate of potash uses a crystallized form of potash to fertilize plants. It does so without leaching into the soil, since most of the potash is absorbed at the ground surface level.
Magnesium is an additional nutrient to plants besides the NPK. Magnesium is important in plants chlorophyll build up and protoplasm components. Depletion of magnesium will cause the plant leaf become yellowish and die.
Basically, a compound fertilizer is one that has several elements included or mixed like boron,copper,cobalt and many other elements that enhance the growing characteristics of a plant or tree.
Micronutrient fertilizer sources are mostly sulfates for Zn, Cu, and Mn, but chelates are the usual Fe source, and borax and sodium molybdate are used for B and Mo, respectively. Soil pH is the soil property that most influences micronutrient availability, and for all but Mo, the higher the soil pH, the lower is the plant availability. For Mo, liming can actually prevent deficiencies. Other soil properties that are important in bioavailability are organic matter content, especially for Cu, oxidation/reduction conditions, especially for Fe and Mn, soil texture, Fe and Al oxide content and soil moisture conditions.
Soil amendment includes all inorganic and organic substances mixed into the soil for achieving a better soil constitution regarding plant productivity. Soil amendment does not include mulching, which includes substances lying on top of the soil. There are different substances for different soils and plants to optimise the soil conditions. A very common amendment is the addition of organic matter like compost, due to its low production costs.
- increase aeration
- increase drainage
- decrease excessive water holding capacity
- decrease or increase weight.
A microbial inoculant known as Effective Microorganisms or EM is a mixed culture of naturally-occurring, beneficial microorganisms (predominantly lactic acid bacteria, yeast, actinomycetes, photosynthetic bacteria and certain fungi) that has been used with considerable success to improve soil quality and the growth and yield of crops, particularly in nature farming and organic farming systems.