DAP Fertilizer: A Nutrient Rich Fertilizer

DAP Fertilizer
DAP Fertilizer

What is DAP fertilizer: A Brief Introduction?

First we discuss the abbreviation DAP, it is short name of diammonium phosphate. DAP is used as best fertilizer for different crops and plants. DAP Fertilizer is mainly composed of phosphorous and nitrogen element that are very essential for the growth of plants. The growth, development and health of plants depends on phosphorous content present in the soil. Nitrogen is the important part of proteins that is why the plants need nitrogen. To provide plants with phosphorus content and nitrogen content DAP Fertilizer is in demand nowadays and is best source of phosphorous. The farmers use it in agriculture in great deal to grow their crop’s productivity and yield.

What is the chemical formula and structure of DAP Fertilizer?

As every chemical has a unique chemical formula so DAP Fertilizer also has a unique chemical formula and that is (NH4)2HPO4. As it is obvious from its chemical formula that is made of ammonium and phosphate ions (NH4+ & HPO4-2). One Phosphate ion bonds with two ammonium ions through ionic bond and forms one ammonium phosphate molecule called diammonium phosphate due to two ammonium ions.

Structural Formula of DAP Fertilizer
3D Structure of DAP Fertilizer

What are physical and chemical properties of DAP Fertilizer

The physical and chemical properties of DAP Fertilizer are unique and we discuss them here one by one.

Physical properties of DAP Fertilizer

  • This chemical fertilizer is colorless or white crystalline granule
  • This is well soluble in water
  • The density may vary however common density is 1.62 g/cm3.
  • It melts at about 155 degrees Celsius.
  • It is a little bit acidic in nature due to ammonium ions

Chemical Properties of DAP Fertilizer

As we discussed it above that its components are ammonium ions and phosphate ion, that are composed of hydrogen, nitrogen, oxygen and phosphorous atoms. It acts as a buffering agent helping in maintaining the pH of soil from a little bit acidic to neutral. When DAP Fertilizer is added to the soil, it combines with it just dissolving and dissociating into phosphate and ammonium ions. You can use it with other fertilizers but should be cautious while using with other chemicals to prevent any site effects or reactions.

What are the Types of DAP Fertilizer?

As DAP Fertilizer is present in the form of granules, so its types are two on the basis of the size of granules namely granular DAP and powdered DAP. Granular DAP has large size granules and the Powdered DAP is present in the form of powder due to small size of its particles.

There is no difference in their chemical composition and nutrient sources but their size of granules, however the powdered DAP can release it nitrogen and phosphorous more rapidly that granular due to its fast solubility in water.

How DAP Fertilizer works?

DAP Fertilizer provides different important food components to the crops and plants needed for growth and sustainability i.e. nitrogen and phosphorous. As it is composed of ammonium and phosphate ions, so ammonium ion provides nitrogen content to plants required for protein synthesis, chlorophyll and enzyme preparation. As phosphorous is an essential agent growth of plants, ATP transfer, growth of flowers and whole development of plants, so phosphate ion provides it.

In short DAP fertilizer provides the plants with phosphorous and nitrogen contents that are absorbed through the roots and used for healthy growth.

How DAP Fertilizer is synthesized?

The process of synthesis of DAP involves the reaction of phosphoric acid (H3PO4) and ammonia (NH3). The process of preparation DAP Fertilizer follows the following general steps. 

  • First ammonia is synthesized by the Haber process in which at high temperature and pressure nitrogen gas reacts with hydrogen gas in the presence of catalyst to synthesize ammonia.
  • Phosphate rocks go through a series of reactions in the presence of sulfuric acid to synthesize phosphoric acid.
  • In the last step neutralization reaction occurs between ammonia and phosphoric acid to make diammonium phosphate.

                                      H3PO4 + 2NH3 → (NH4)2HPO4

  • Granulation or Drying:

After the production, the diammonium phosphate can be further changed into granular or powdered. Granulation process involves changing the DAP into granules, that are then dried to release left-over moisture and ensure product stability.

  • Quality Control: During the whole synthesis process, quality control steps are involved to ensure the purity, nutrient content, and physical properties of the DAP fertilizer meet industry standards and regulatory needs.

How to use Diammonium Phosphate Fertilizer?

It is necessary to know how to use DAP Fertilizer properly for efficient crop products, the steps to be followed during application of diammonium phosphate fertilizer are given below.

  • One must test the soil before applying the DAP to the crops to identify the PH and nutrient contents in the soil.
  • One should determine the application rate through soil test that how much and how many times one should use the DAP in a year
  • The time is also important, so it is suitable to add the DAP Fertilizer to the soil before sowing the seeds or it may be use during sowing or after sowing the seed.
  • It should not be applied to standing crops, rather it should be applied before sowing the seeds or during sowing the seeds.

Application methods of DAP Fertilizer

  • Broadcasting: It should be spread evenly and equally all over the soil surface
  • For row-crops and deep-rooted plants it is emphasized to apply near the plants for greater and efficient absorption.
  • The powdered DAP Fertilizer may be sprayed directly to the leaves by spraying but it is not encouraged due to low absorption.
  • To help dissolve the nutrients into the soil one should water the soil, it will increase the uptake of nutrients by the plants.
  • One should mentor the whole growing process, making adjustments in quantity of DAP Fertilizer.

Safety Precautions while using DAP Fertilizer

The DAP should be handled carefully, one should wear eyeglasses, gloves, mask and avoid skin contact during its application.

It must be kept away from children, pets, drinking and food materials to avoid any misshaping.

DAP Fertilizer Compatible Plants and crops

Large number of plants are compatible with DAP Fertilizer, however a list of some common plants are given below that are compatible with DAP.

  • Rice.
  • Wheat:
  • Maize:
  • Soybean:
  • Cotton:
  • Sugarcane:
  • Pulses (Chickpea, Lentil, Peas)
  • Potato
  • Vegetables (Tomato, Brinjal, Capsicum)
  • Fruits (Mango, Banana, Citrus)
  • Tea and Coffee


How does DAP Fertilizer work?

It works by providing the plants and crops with nitrogen and phosphorous contents that the plants need to grow and develop.

What is the difference between DAP and MAP Fertilizer?

DAP contains two ammonium ions in its molecule but MAP has only one molecule in its molecule. DAP is more acidic than MAP. DAP is suitable for plants that need acidic soil to grow. MAP is suitable for plants that need alkaline soil to grow.

What are the advantages of using DAP Fertilizer?

  • High Nutrient Content: DAP contains reliable sources of phosphorus (HPO4) and is easy to store.
    • Quick Action: It works quickly and benefits various crops.
    • Inertness: Phosphorus in DAP is not lost via leaching due to its inertness in the soil.

You may like to read about soil conservation by clicking the link https://www.thesciencepool.com/soil-conservation/

For more information related to diammonium phosphate fertilizer you may visit the link given below https://www.cropnutrition.com/resource-library/diammonium-phosphate/

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