Growing Cashew Nuts in Kirinyaga

Soil suitability analysis based on Kirinyaga's nutrient profile

Kirinyaga County is a challenging environment for Cashew Nuts (soil-match score 9/100) and will need significant amendment before planting. Local soils average pH 5.31 — moderately acidic and inside the 5–7.5 band Cashew Nuts prefers, so no lime is usually required. Nitrogen (1.36 g/kg), phosphorus (12.5 mg/kg) and potassium (177 mg/kg) all meet Cashew Nuts's requirements, so a maintenance fertilizer programme is enough. Cashew Nuts prefers sandy soils, while Kirinyaga is largely clay, so drainage and organic-matter management matter more here. At 1500 m, the county sits above Cashew Nuts's preferred altitude ceiling of 500 m, where frost risk and cold nights reduce the crop's productivity. Cashew Nuts's full potential is about 900 kg/acre (~KES 247,500/acre at KES 275/kg), but at Kirinyaga's 9/100 suitability a realistic target here is closer to 101 kg/acre (~KES 27,775/acre) unless the constraints above are addressed.