Growing Coffee (Robusta) in Kirinyaga

Soil suitability analysis based on Kirinyaga's nutrient profile

Coffee (Robusta) can be grown in Kirinyaga County, but the soil scores 49/100 and needs targeted management to reach full potential. Local soils average pH 5.31 — moderately acidic and inside the 5–6.5 band Coffee (Robusta) prefers, so no lime is usually required. The main gap is potassium — measured at N 1.36 g/kg, P 12.5 mg/kg, K 177 mg/kg against this crop's high/medium/high demand — so the fertilizer plan below prioritises closing that deficit. Coffee (Robusta) prefers loam soils, while Kirinyaga is largely clay, so drainage and organic-matter management matter more here. At 1500 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. At current prices (about KES 80/kg) and a typical 950 kg/acre yield, a well-managed Coffee (Robusta) crop here can gross roughly KES 76,000 per acre.