Fertilization for Rubber Plantations: Principles and Management

Section I. General Regulations

Fertilization for rubber plantations must comply with both management and technical standards, ensuring quality, proper nutrient balance, and minimizing fertilizer losses to maintain high efficiency.
Fertilizers derived from peat are strictly prohibited.

1. Fertilizer Management by Plantation Type

• For immature rubber plantations (KTCB phase):
  Fertilization must be adjusted based on soil condition and tree growth status.

  • Reduce fertilizer for vigorous areas;

  • Increase for weak or poor-growing zones;

  • Ensure the total fertilizer volume does not exceed VRG’s annual limit.

• For mature (tapping) rubber plantations:
  Adjust fertilization according to:

  • Actual tree growth and productivity;

  • Soil nutrient analysis results (if available);

  • Fertilization history and other technical factors.

2. Fertilization Guidelines

• Only fertilize after weed control is ensured.

• Mechanized fertilization is encouraged in suitable terrains.

• Apply nutrient-diagnostic fertilization to save costs and enhance nutrient efficiency.

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Article 84. Fertilizer Quality Control

Only fertilizers meeting national technical standards (QCVN) and VRG’s internal quality control regulations are permitted for use.

1. Quality Requirements

• Inorganic fertilizers:
  Nutrient content deviations must not exceed national tolerance limits.

• Organic fertilizers:

  • Moisture ≤30%

  • Organic matter ≥20%

  • C/N ratio ≥12

  • Heavy metals (As, Pb, Hg, Cd) and pathogens (Salmonella, E. coli) must remain below legal thresholds.
    (Refer to Appendix IX for detailed nutrient standards and permissible deviations.)

2. Locally Produced Fertilizers

• Fertilizers produced internally by member companies may only be used if:

  • Certified under national standards (QCVN),

  • Possess valid production permits, and

  • Meet VRG’s inspection criteria.

3. New Fertilizer Types

• Any new fertilizer type introduced for the first time within VRG must have:

  • Clear origin and manufacturer compliance with state regulations,

  • Completed field trials, and

  • Received VRG approval before large-scale use.

4. Sampling and Procurement Management

• Companies must follow VRG’s fertilizer sampling protocol and send samples for independent testing.

• Units are responsible for quality verification and acceptance testing of all fertilizers, including internally made products.

• Fertilizer supply contracts must specify:

  • Type and formulation,

  • Nutrient concentrations,

  • Tolerance limits — forming the basis for quality inspection and acceptance testing.

Transparency in fertilizer quality ensures consistent tree growth and efficient nutrient uptake across all VRG plantations

1. Annual Fertilization Plan

• In Quarter I each year, each unit must prepare a detailed fertilizer plan including:

  • Type, rate, and total amount of fertilizer;

  • Allocation by plantation age group;

  • Submission to VRG Headquarters for review and approval prior to implementation.

2. Field Fertilization Plan and Monitoring

• Before each fertilization round, companies must:

  • Prepare field-level fertilization schedules for every plot;

  • Assign supervisors to monitor workers and prevent fertilizer loss or uneven application.

3. Technical and Documentation Requirements

• Fertilization must ensure the “5 Rights”:

  1. Right fertilizer type

  2. Right dose

  3. Right method

  4. Right place

  5. Right timing

• On flat lands: fertilizer must be buried in soil.

• On sloped areas: fertilizer is applied into designated pits to prevent runoff.

• Each application must be recorded with a verification report, including:

  • Type and quantity of fertilizer,

  • Person in charge,

  • Supervisor’s name.

  • Post-application reports are submitted to VRG.

Proper management not only improves nutrient efficiency but also safeguards soil structure and minimizes environmental impact.