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2 Fertilizer Tools

The team at OFRA has been working on a number of tools that can be used to support better guidelines for smallholder farmers.

The Fertilizer Calibration Tool is a really useful to anyone wanting to make a farmer-friendly recommendation about fertilizer use. It allows you to measure any container available to the farmers you are working with, and then it uses stored information on the different densities of the different fertilzers to advice them on the application rate for the matchbox or jerry can lid they use as their measure for fertilizer. Guides to fertilizer application are often wrong because writers fail to understand that the same weight of different fertilizers may have very different volumes.

The Fertilizer Optimisation Tool has a different approach from much of the previous work as it pursues profit maximisation rather than yield maximisation. The smallholder provides information on area of each crop to be planted and its expected value, fertiliser cost estimates, and money available for fertilizer use. The tool optimises across various crop-nutrient functions and allocates available money to the crop-nutrient-rate options that is likely to give the most profit. The tool is adapted for targeted agro-ecological zones (AEZ) by changing crops considered and drawing on different researched response functions.

The OFRA Trial Protocol document will show you how the team assured quality and consistency in the development of the field trials that generated the fertilzer response curves, used to generate the Fertilizer Optimisation Tool.