An analysis of in‐field soil testing and mapping for improving fertilizer decision‐making in vegetable production in Kenya and Ghana

Abstract

Agriculture in Sub-Saharan Africa faces abundant challenges, among others low crop yields estimated at 1.5 t ha −1 for cereals compared to a global average of 3.5 t ha −1 (FAO, 2015). This is primarily due to the sector's dependence on variable rainfall (Chauvin et al., 2012) and low application rates of mineral fertilizers, with Ghana and Kenya applying 23.8 and 28.6 kg ha −1 to arable land, respectively, compared with the global average of 137.6 kg ha −1 (World Bank, 2018).

Why Agricultural Tools Work in Theory But Aren’t Adopted in Practice: A Grounded Theory Approach to ICT in Ghana and Kenya

“…Using a fine filter paper did remove the reddish hue from the filtrate, but added hours to a technology whose entire premise was speed. Other options that could advance its ability would have included using syringe filters where pressure could be applied instead of waiting for gravity settling, or using soil extractants (Golicz et al, 2021; Mallory et al, 2022). Both of these options would have also added to the cost and time per sample which stood at £0.90 per sample for a strip and filter paper already.…”

“…A short overview of the soil testing method is given here to inform the results section and the reflections on the practicality of the tool. More details can be found in (Mallory et al, 2022). The intended research method was to take 10 g of soil from a farm area that was about to have fertiliser applied and seeds planted.…”

“…In journals that review technology, even those that explicitly claim to be interdisciplinary, there is often an attitude that qualitative data 'isn't science' or 'are just opinions'. In an environment characterised by these issues the technical viability of the soil testing intervention was published as a separate paper (Mallory et al, 2022) potentially exacerbating the adoption of such technologies and echo chambers amongst technology advocates and advocates for understanding context first.…”

“…However, the demand for and revenue from this kind of fertiliser is not yet sufficient to drive improvements for sanitation further up the chain (Mallory et al, 2020). One potential barrier to the adoption of human-waste derived fertiliser (HWDF) by farmers is its nutrient variability, which may make targetted application more difficult than with current chemical fertilisers of set ratios of nutrients (Golicz et al, 2019; Mallory et al, 2022). To avoid over application of nutrients that can lead to both wasted resources in a farm context and nitrogen run off that leads to pollution of water bodies, one potential solution is the use of in-field soil testing which can yield quick soil assessments (Golicz et al, 2021; Nyi et al, 2017).…”

“…This paper presents findings from a project investigating the use of nitrate-sensitive paper strips alongside Akvo Caddisfly (an app that temporarily turns a smartphone into a portable reflectometer), to understand farmers perceptions and willingness to adopt such technologies in Kenya and Ghana (Mallory et al, 2022). The paper uses a grounded theory approach to examine these issues and to locate the process of app adoption within an understanding of how farmers currently use and share information within agronomic decision-making.…”