Inorganic fertilizers, also known as synthetic or chemical fertilizers, are manufactured products that provide essential nutrients to plants.
These fertilizers are made from various chemical compounds and are designed to supplement the nutrient requirements of plants.
Inorganic fertilizers typically contain three primary nutrients: nitrogen (N), phosphorus (P), and potassium (K).
These nutrients are often referred to as NPK and are represented by three numbers on fertilizer labels, such as 10-10-10 or 20-5-10, indicating the percentage of each nutrient present in the fertilizer.
Nitrogen (N) promotes leaf and stem growth, phosphorus (P) supports root development, flowering, and fruiting, while potassium (K) aids in overall plant health, water regulation, and disease resistance.
Inorganic fertilizers can also include secondary nutrients like calcium, magnesium, and sulfur, as well as trace elements like iron, manganese, zinc, and copper.
Inorganic fertilizers are manufactured through various chemical processes, which may involve extracting minerals from natural sources, such as rock phosphate for phosphorus or potassium chloride for potassium.
These minerals are processed to create a soluble form that can be easily absorbed by plants. The resulting fertilizer products are generally readily available and provide a quick nutrient boost to crops.
While inorganic fertilizers can effectively improve plant growth and increase crop yields, their usage also raises environmental concerns.
Excessive or improper application of these fertilizers can lead to nutrient runoff into water bodies, causing water pollution and harmful algal blooms.
Additionally, their production often requires energy-intensive processes and contributes to greenhouse gas emissions.
USES OF INORGANIC FERTILIZERS IN AGRICULTURE
inorganic fertilizers are one of the very rich sources of soil plant nutrients.
one of the reasons for the application of inorganic Fertilizers is that they help to increase the yield of crops, and improve the structure of the soil
(iii) They increase the activities of soil organisms while also improve soil aeration
(v) They increase the fertility of the soil
(vi) They increase the growth of plankton in fish ponds.
Types of inorganic Fertilizers
Fertilizers are grouped into two major classes based on their composition:
(i) Straight or Single Fertilizers: These fertilizers contain only one element. Such element may be nitrogen, phosphorus and potassium.
(a) Fertilizers which are rich in nitrogen are called nitrogen fertilizers and examples include:
(1) Animonlum sulphate – (NH4),SO, 21%N,24%S
(2) Ammonium nitrate – NH4NO, 335%N
(3) Urea – CO(NH,), 46%N
(4) Sodium nitrate – NaNO, 16%N
(5) Potassium nitrate,
(6) Anhydrous ammonia,
(7) Ammonia liquor
(8) Calcium ammonium nitrate
(9) Diammonium phosphate.
(b) Fertilizers which are rich in potassium are called potassium fertilizers and an example is nitrate of potash – Kcl 50%K2O inorganic fertilizers
(c) inorganic Fertilizers which are rich in phosphorus are called phosphorus fertilizers and examples include:
Single super phosphate – CaNPO, 43.7%P
Triple super phosphate – 45%.
Guano (poultry/bird droppings).
Complete or Mixed or Compound Fertilizers: These are inorganic fertilizers which contain two or more nutrients. A good example is inorganic fertilizers
N.P.K. fertilizer, which contains nitrogen, phosphorus and potassium. Compound fertilizer can exist in various combinations such as 15-15-15, 20-5-10 and 5-10-5. 15-15-15 grade would have an l:1:1 ratio of N: P,O, K2O. 15.15.15. means equal amounts of nitrogen, phosphorus and potassium.
METHODS OF INORGANIC FERTILIZER APPLICATION
Different methods are used to apply fertilizers to the soil. These include:
(1) Broadcasting: This is the ground before they are ploughed into the soil.
(2) Ring method: A circular hole is made around the crop and fertilizer is placed inside the hole after which the hole is covered.
The circular hole must not come too close to the plant, otherwise, fertilizer will touch the plant and burn it.
(3) Row or side placement: Make a hole a few centimetres from each plant and apply a teaspoonful of fertilizer per plant in each hole, then cover it up with soil.
read how to properly apply fertilizer here
(4) Top dressing: This refers to the second application of fertilizer several weeks after the first dose had been applied. The second does it to supplement the first application.
(5) Folial spray: this is the method in which some trace elements or micro-nutrients are dissolved in water and sprayed on the crop directly. The leaves are capable of absorbing the nutrients directly into their body.