This tool is oriented to the calculation of N, P and K fertilizer rates by farmers and agronomists.

Left: Input form for FertiliCalc 3.3 (French version). Right: Results form for FertiliCalc 3.3 for Windows (French version)

FertiliCalc is a program developed at IAS-CSIC and Universidad de Cordoba to help in calculating N, P and K fertilizer rates. It also provides estimates of soil acidification and N losses. The smartphone version (Fertilicalc 4.0) includes 18 languages. The Windows version (FertiliCalc 3.3) is available in 91 languages and includes the manual and reading materials. Tutorials in English and Spanish are also available in Youtube. The algorithms are based on several chapters of the book “Principles of Agronomy for Sustainable Agriculture” by Villalobos & Fereres (2017, Springer) and explained in detail in Villalobos et al. 2020 (https://doi.org/10.1007/s42106-019-00085-1).

The program offers a wide list of crops to add to the rotation. The user adds soil data (if available) and decides the strategy to follow for P and K fertilization. Then the fertilizers to apply before and after planting are selected. Rainfall is considered for calculating expected N leaching. The program assigns a value based on location. Finally, the results (fertilizer rates, N losses, soil acidification) are presented.  FertiliCalc allows the users to determine the best complex fertilizer for pre-plant applications to avoid blending of simple fertilizers at the farm, a task usually complex for farmers.

This program is being used as a teaching tool in several universities around the world. It’s also the basis for several fertilizer calculation apps developed by public institutions in Spain.

Contact: fvillalobos@uco.es; alopez@ias.csic.es

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