Growing Coffee (Robusta) in Machakos

Soil suitability analysis based on Machakos's nutrient profile

Machakos County is a challenging environment for Coffee (Robusta) (soil-match score 14/100) and will need significant amendment before planting. At an average pH of 7.03 the soil sits above Coffee (Robusta)'s preferred 5–6.5 range, which can limit uptake of phosphorus and micronutrients. The main gap is nitrogen — measured at N 0.82 g/kg, P 31.4 mg/kg, K 338 mg/kg against this crop's high/medium/high demand — so the fertilizer plan below prioritises closing that deficit. The county's predominantly sandy loam soils suit Coffee (Robusta), which favours loam. Machakos receives approximately 700 mm/year — well below Coffee (Robusta)'s minimum of 1500 mm — so supplemental irrigation would be essential for this crop. Coffee (Robusta)'s full potential is about 950 kg/acre (~KES 76,000/acre at KES 80/kg), but at Machakos's 14/100 suitability a realistic target here is closer to 166 kg/acre (~KES 13,280/acre) unless the constraints above are addressed.