Growing Coffee (Robusta) in Kisii

Soil suitability analysis based on Kisii's nutrient profile

Kisii County is a challenging environment for Coffee (Robusta) (soil-match score 42/100) and will need significant amendment before planting. Local soils average pH 5.21 — moderately acidic and inside the 5–6.5 band Coffee (Robusta) prefers, so no lime is usually required. The main gap is nitrogen and potassium — measured at N 1.09 g/kg, P 13.1 mg/kg, K 151 mg/kg against this crop's high/medium/high demand — so the fertilizer plan below prioritises closing those deficits. The county's predominantly clay loam soils suit Coffee (Robusta), which favours loam. At 1700 m, the county sits above Coffee (Robusta)'s preferred altitude ceiling of 1200 m, where frost risk and cold nights reduce the crop's productivity. Coffee (Robusta)'s full potential is about 950 kg/acre (~KES 76,000/acre at KES 80/kg), but at Kisii's 42/100 suitability a realistic target here is closer to 499 kg/acre (~KES 39,920/acre) unless the constraints above are addressed.