A soil test costs less than one bag of fertilizer, yet most cassava farmers skip it entirely and guess instead. That guess gets expensive fast, since applying the wrong fertilizer or lime can waste an entire season’s input budget.

Cassava root looks like a rough, unremarkable brown tuber, yet beneath that skin sits one of the most important food crops on Earth, feeding hundreds of millions daily and quietly powering flour, starch, and biofuel industries across the globe.