Growing Stevia in Kirinyaga

Soil suitability analysis based on Kirinyaga's nutrient profile

Kirinyaga County is a solid choice for Stevia, with a soil-match score of 67/100. At an average pH of 5.31 the soil is moderately acidic, below Stevia's preferred 6–7.5 range; agricultural lime will lift pH and unlock phosphorus the crop cannot otherwise access. Nitrogen (1.36 g/kg), phosphorus (12.5 mg/kg) and potassium (177 mg/kg) all meet Stevia's requirements, so a maintenance fertilizer programme is enough. Stevia prefers loam soils, while Kirinyaga is largely clay, so drainage and organic-matter management matter more here. Stevia's full potential is about 3,000 kg/acre (~KES 600,000/acre at KES 200/kg), but at Kirinyaga's 67/100 suitability a realistic target here is closer to 2,513 kg/acre (~KES 502,600/acre) unless the constraints above are addressed.