1、Fertilizer Calculations for Greenhouse Crops

For example, it is often recommended that 150 to 250 ppm N be applied in the irrigation water on a "constant feed" basis for fertilizing many floricultural crops. But what actually does this mean?

2、How to Properly Use Macro

The macro-element water-soluble fertilizer can be divided into balanced, high-nitrogen, high-phosphorus, high-potassium and special fertilizers according to the different proportions of its elements.

3、How to Fertilize Garlic with Macro

Based on garlic’s growth stages and soil fertility, apply 5–10 kg of macro-element water-soluble fertilizer per mu (0.066 hectares) to meet its needs throughout the cycle.

The Basics of Fertilizer Calculations for Greenhouse Crops

This guide outlines the principles of meeting plant nutrient needs through proper fertilizer selection, formulation, and application. Plants require 17 essential elements for growth, with fertilizers providing the mineral nutrients not derived from air or water.

Macroelement Water Soluble Fertilizer – LOXOWO

Product Effect: Comprehensive nutrition, quick effect, promote growth and anti-aging Product Usage: Flushing, drip irrigation :2.5-5 kg/mu, the whole growth cycle used 23 times.

How to choose the right macroelement water soluble fertilizer

According to the standard of macroelement water-soluble fertilizer, the single nutrient content of nitrogen, phosphorus and potassium should not be lower than 4%, and the sum of these three should not be lower than 50%. If one of the macroelement is marked on the package is less than 4%.

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Fertilizer recommendations are most often given in terms of the concentration of a desired element in the irrigation water. This con-centration is expressed as parts per million (ppm). For example, you may use a 20-10-20 fertilizer on poinsettias to supply nitrogen at a concentration of 300 ppm.

Water Soluble NPK Fertilizers

Like all soluble fertilizers, the normal rate of dilution in the final irrigation water is 1 gram per litre. Whilst this is the normal rate, this rate can be varied. For sensitive species or very young plants, the rate is reduced – typically to 0.5 gram per litre.

WATER

Water-soluble fertilisers can be directly diluted into the irrigation water in bulk tanks, spray tanks, bowsers, etc. In this situation the required amount per litre is applied directly into the tank, with good agitation.

How to Choose Macroelement Water Soluble Fertilizer

In agricultural applications, the application of fertilizers is always indispensable for crops. Fertilizers can give crops the nutrients they need and promote their growth.

The amount of macro-element water-soluble fertilizer to apply per mu (approximately 0.067 hectares) depends on soil conditions, crop requirements, and the specific composition of the fertilizer. Below is a detailed guide to determining the appropriate fertilizer quantity and specific recommendations.

I. Understanding Soil Conditions

1. Soil Type

• Loamy Soil: Retains water and nutrients well. Use slow-release fertilizers, such as nitrogen-phosphorus-potassium compound fertilizers.
• Sandy Soil: Drains quickly but loses nutrients easily. Opt for fast-acting fertilizers, like high NPK water-soluble varieties.
• Clay Soil: Poor in water/nutrient retention and prone to compaction. Improve with organic fertilizers and microbial agents to enhance structure and organic matter.

2. Soil pH

• Acidic Soil (pH < 6): Use sulfur-based or lime-based fertilizers to neutralize acidity.
• Alkaline Soil (pH > 7): Avoid calcium/magnesium-containing fertilizers to prevent further alkalinization.

II. Crop Requirements

1. Crop Type

• Economic Crops (e.g., cotton, tomatoes): Require high nitrogen (N) and potassium (K) for fruit/flower development.
• Grain Crops (e.g., wheat, corn): Need balanced NPK ratios for root growth and grain filling.
• Fruit Trees: Require NPK plus microelements like iron (Fe), zinc (Zn), and manganese (Mn).

2. Growth Stage

• Seedling Stage: Prioritize nitrogen for root/leaf development.
• Vegetative Stage: Balanced NPK for healthy stems/leaves.
• Flowering/Fruiting Stage: Emphasize phosphorus (P) and potassium for quality yields.

III. Fertilizer Composition

1. Nitrogen (N) Sources

• Urea: Rapidly promotes growth and yield.
• Ammonium Nitrate: Suits crops with fast nitrogen uptake.
• Nitrate Nitrogen: Ideal for nitrate-loving crops (e.g., tobacco, beets).

2. Phosphorus (P) Sources

• Superphosphate: Suits slow-P-absorbing crops.
• Double Superphosphate: Best for acidic soils to raise pH.
• Calcium Hydrogen Phosphate: 优选 for calcium-loving crops (e.g., legumes, potatoes).

3. Potassium (K) Sources

• Potassium Sulfate: Versatile for fast-K-absorbing crops.
• Potassium Chloride: For chloride-tolerant crops (e.g., tobacco, beets).
• Potassium Magnesium Sulfate: Beneficial for magnesium-demanding crops (e.g., potatoes, sunflowers).

IV. Calculating Fertilizer Dosage

1. Fertilization Principles

• Small Doses, Frequent Applications: Avoid over-fertilization risks.
• Balanced Formulas: Ensure NPK ratios align with crop needs.
• Scientific Proportions: Base on soil tests and crop demands.

2. Application Methods

• Base Fertilizer: Pre-plant for long-term nutrient supply.
• Topdressing: Mid-season adjustments based on crop health.
• Foliar Spraying: For rapid nutrient absorption and higher efficiency.

3. Dose Calculation

• Local Guidelines: Follow regional agricultural standards adjusted via soil tests.
• Soil Testing: Analyze nutrient levels to inform dosage.
• Crop Analysis: Tailor amounts to growth cycles and requirements.

V. Key Considerations

1. Timing

• Pre-sowing: Ensures nutrient availability for germination.
• Early Growth: Boosts development and yield potential.
• Flowering/Fruiting: Supports quality and reduces defects.

2. Application Methods

• Ditch Application: Fertilizer spread in furrows before covering.
• Hole Application: Direct placement in planting holes (avoid excess).
• Foliar Spraying: Efficient for large-leaf crops with rapid uptake.

3. Monitoring Effects

• Crop Health: Regularly assess growth to evaluate effectiveness.
• Soil Tests: Track nutrient changes for future adjustments.
• Pest Management: Proper fertilization reduces disease/pest risks.

VI. Conclusion & Recommendations

The optimal dose of macro-element water-soluble fertilizer per mu depends on soil, crops, and formula. Prioritize scientific principles, balanced formulas, and timely applications. Combine soil testing with crop monitoring to maximize results while minimizing environmental impact.