Precise Fertilization Techniques for Oil Palm Production: Applying the Four Right Principles (4T)

Authors: Anggri Sentia Br Barus, Novella Angelica Hutagalung, Muhdan Syarovy, Wan Riski Fauzi | Year: 2025 | DOI: https://doi.org/10.22302/iopri.war.warta.v30i1.129

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Fertilization is one of the largest cost components in oil palm (Elaeis guineensis) plantation management, accounting for 40–60% of total production costs. Ironically, most of the applied fertilizers are not optimally absorbed by the plants due to errors in timing, dosage, type, or application method. The principle of Four Rights (4R), the right type, the right dose, the right time, and the right method, has long been known as a guiding framework, but its implementation in the field often remains a challenge.

This article discusses the practical application of the 4R principle specifically for productive oil palm plants (TM), which are trees that have entered the production phase. Unlike non-productive plants (TBM), TM trees have much higher nutrient requirements and different root distribution patterns, so their fertilization strategy must be adjusted. This article summarizes research and field experiences from the PPKS team, which has worked in various land conditions in Indonesia.

From the aspect of right type, this study emphasizes the importance of regular leaf and soil analysis to determine the most suitable fertilizer type for specific plantation conditions. There is no single formula that applies to all conditions. For right dose, a leaf sampling unit (LSU)-based approach and dynamic fertilizer recommendations have proven to be more efficient than uniform standard doses. Right time is closely related to rainfall distribution, with fertilization being most effective when the soil is sufficiently moist but not waterlogged, ideally 2–4 weeks after the start of the rainy season. Right method includes placing fertilizers in the tree basin, avoiding direct contact with the trunk, and using the pocket system for higher efficiency.

The following is a summary of the factors studied, their roles, and levels of influence.

Factor	Role in Research	Condition / Context	Level of Influence	Specific Findings
Right Type	The first pillar of 4T: choosing the right type of fertilizer that matches the specific deficiency at the location	Determined through leaf analysis (leaf sampling) and soil analysis conducted periodically in each garden block	Very High	There is no single fertilizer formula that applies to all land conditions. Gardens with peat, mineral, or sandy soils require different types of fertilizers
Right Dose	The second pillar of 4T: determining the optimal amount of fertilizer based on the actual needs of the plant, not generic estimates	Calculated using the Leaf Sampling Unit (LSU) approach and updated fertilizer recommendations every season	Very High	The LSU-based approach has proven to be more efficient and cost-effective compared to using a uniform standard dose that does not consider variations in conditions between blocks
Right Time	The third pillar of 4T: synchronizing the fertilization schedule with rainfall conditions so that fertilizers can be absorbed optimally	Ideal time: 2-4 weeks after the start of the rainy season, when the soil is moist but not flooded	Significant	Fertilizing when the soil is too dry: fertilizers do not dissolve. When the soil is flooded: the risk of nutrient leaching is high. Synchronization with weather forecasts is very helpful
Right Method	The fourth pillar of 4T: application methods that minimize fertilizer loss and maximize absorption by the roots	Placement in the tree basin (not on the trunk), pocket system method for higher efficiency	Significant	Pocket system method: fertilizers are buried in holes around the basin, reducing loss due to surface runoff and evaporation compared to the conventional broadcasting method
Fertilizer Cost Efficiency	Direct impact of 4T implementation: reduction of input costs and increased productivity	Fertilization is 40-60% of the total production cost – the largest cost component in oil palm gardens	Limited	Consistent implementation of 4T also reduces the risk of nutrient leaching into water bodies, providing environmental benefits in addition to economic benefits

The consistent application of the 4T principle not only increases the efficiency of fertilizer use and reduces production costs, but also has a positive impact on the environment by reducing the risk of nutrient leaching into water bodies. For plantation companies and independent farmers, a deep understanding of this principle is a knowledge investment that yields long-term benefits.

Do you have questions about this research or similar experiences in your plantation? Write in the comments column, we’re happy to discuss.

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