For more than two decades, the sugarcane sector of Valle del Cauca, Colombia, has served as a living laboratory for precision agriculture. This is not a story about theoretical pilots or futuristic promises. It is a story about maps, models, machines, data and measurable results. Yet, as of 2024, less than 10% of the sugarcane area applies variable-rate fertilization, despite consistent evidence of yield gains, input optimization, and reduced environmental footprint.

 

Fertilizer costs typically represent 20–30% of total production costs in sugarcane an economically sensitive component where every recommendation and every kilogram applied matters. The question, therefore, is no longer whether precision agriculture works. The real question is: why are we not adopting it on a scale?

 

In 2007, the first large-scale geostatistical studies were conducted in the sugarcane region of southwestern Colombia. More than 20,000 hectares were mapped, revealing an uncomfortable but undeniable truth: soil is not homogeneous and it never has been.  Even after years of detailed soil surveys at 1:10,000 scales, the results showed even greater variability when physiographic changes across the landscape were properly accounted for. This represented a fundamental shift. From that moment on, mathematical models were developed to recommend fertilizers and soil amendments based on spatial variability rather than field averages.

 

Fertilizer spreaders equipped with GPS and electronic controllers were integrated to adjust application rates in real time. Harvesters were instrumented to generate yield maps, allowing agronomists to verify responses, close the feedback loop, and continuously refine management strategies. Agriculture shifted from a reactive mindset to an analytical one.

 

In a pilot program covering approximately 12,353 hectares, with disciplined monitoring over four consecutive years, the results were unequivocal. On an annual basis, the program achieved optimization of approximately 515 tons of urea and 28 tons of potassium chloride, while delivering an average yield increase of more than +10 t/ha in areas managed with variable-rate fertilization.

 

Climate variability certainly influenced absolute yields, but the productivity advantage of variable-rate management persisted under wet, dry, and normal years alike. These results confirm that variable-rate technology does more than reduce inputs it reconnects crop nutrition with the true productive potential of the soil.
 
Subsequent implementations of the same tools in other Colombian sugar mills, as well as in sugarcane operations in Costa Rica and Ecuador, yielded comparable outcomes. Beyond optimizing nitrogen, phosphorus, and potassium inputs, these projects enabled the identification of zones constrained by low or high pH, the adjustment of mechanized operations according to clay and sand variability, and better alignment of management practices with effective rooting depth and usable soil volume.

 

Environmental impact indicators further reinforced the value proposition. The evidence is clear and consistent: variable-rate application is not only profitable, but also resilient under diverse climatic conditions and aligned with sustainability objectives.  The following table illustrates the impact of variable-rate application on the reduction of CO₂ emissions, as well as the lower energy consumption associated with urea production processes. It also demonstrates how fertilizer optimization translates into improved environmental performance of the production system, reinforcing both sustainability and operational efficiency.

 

 

In 2011, a single company surpassed 25,000 hectares managed under variable-rate fertilization. By 2024, the entire sector managed only about 17,000 hectares under this approach, out of nearly 190,000 hectares harvested. This regression occurred despite having more technology, more data, more trained personnel, and stronger scientific evidence than ever before.

 

This is not a technical problem. It is a cultural and strategic one.

 

Precision agriculture is not a trend; it is a new language for understanding farming systems. It is not about maps; it is about decisions. It is not about machines; it is about strategy. It is not only about reducing costs, but also about multiplying value.
 
The question is no longer whether we can do it. The question is whether we are willing to change.

 

Carlos Mosquera. Agriculture Engineer, GIS Specialist. MBA. Colombia - Country Representative ISPA.