OVERVIEW
21 : 7 : 13 fertilizers are nitrogen-dominant NPK formulations designed to support strong vegetative growth, while still providing sufficient phosphorus for root activity and potassium for stress tolerance and crop quality. This type of fertilizer is commonly used in field crops, vegetables, orchards, and forage crops, especially during early and mid-growth stages.
The fertilizer can be produced as either a complex fertilizer (chemically reacted) or a compound fertilizer (physically blended), depending on the manufacturing technology.
COMPOSITION OF 21 : 7 : 13 FERTILIZERS
This formulation is built on three main nutrient groups:
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Nitrogen (N):
Drives leaf growth, canopy development, chlorophyll formation, and biomass production. -
Phosphorus (P):
Supports root development, early plant establishment, and energy transfer. -
Potassium (K):
Improves water regulation, stress resistance, and overall plant strength.
Because nitrogen is dominant, this formulation is particularly suitable where vigorous vegetative growth is required.
RAW MATERIALS USED
Typical raw materials selected for this fertilizer include:
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Nitrogen-based fertilizer materials
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Phosphorus-containing phosphate materials
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Potassium salts with good agronomic compatibility
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Process water (for complex production)
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Granulation binders and conditioners
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Optional trace element premixes
Raw materials are chosen based on purity, compatibility, and granulation behavior.
HOW TO MAKE 21 : 7 : 13 FERTILIZERS
1. COMPLEX FERTILIZER PRODUCTION METHOD
In this method, nutrients are chemically reacted and granulated together.
Main steps
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Chemical reaction of nitrogen and phosphorus sources
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Formation of a nutrient slurry
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Addition of potassium source
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Incorporation of optional trace elements
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Granulation to form uniform particles
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Drying and cooling
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Screening and size control
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Anti-caking coating and packaging
Key advantage:
Each granule contains nitrogen, phosphorus, and potassium in the same ratio, ensuring uniform nutrient distribution.
2. COMPOUND (BLENDING) FERTILIZER METHOD
In compound fertilizers, nutrients are produced separately and then blended.
Main steps
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Preparation of nitrogen, phosphorus, and potassium granules
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Accurate weighing and mixing
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Addition of micronutrients if required
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Screening and conditioning
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Packaging
Key advantage:
Flexible production and lower manufacturing complexity.
PHYSICAL CHARACTERISTICS OF THE FINAL PRODUCT
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Granular, free-flowing structure
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Uniform particle size
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Low dust formation
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Suitable for mechanical spreaders
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Stable during storage and transport
These properties ensure easy handling and efficient field application.
APPLICATION AREAS
21 : 7 : 13 fertilizers are commonly used in:
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Field crops
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Vegetables
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Forage crops
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Orchards
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Lawns and green areas
They are especially effective during vegetative growth periods when nitrogen demand is high.
ADVANTAGES OF 21 : 7 : 13 FORMULATION
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Strong stimulation of vegetative growth
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Balanced support from phosphorus and potassium
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Suitable for intensive farming systems
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Compatible with mechanized application
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Can be enriched with trace elements if needed
SUMMARY
21 : 7 : 13 fertilizers are manufactured by combining nitrogen-rich, phosphorus, and potassium components through complex granulation or compound blending techniques. Their nitrogen-dominant composition makes them ideal for promoting rapid growth and canopy development while maintaining balanced plant nutrition. Proper production ensures uniform granules, high efficiency, and reliable crop performance.
