Growing Sunflower in Kirinyaga

Soil suitability analysis based on Kirinyaga's nutrient profile

Sunflower can be grown in Kirinyaga County, but the soil scores 47/100 and needs targeted management to reach full potential. At an average pH of 5.31 the soil is moderately acidic, below Sunflower'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 Sunflower's requirements, so a maintenance fertilizer programme is enough. Sunflower prefers sandy soils, while Kirinyaga is largely clay, so drainage and organic-matter management matter more here. Sunflower's full potential is about 750 kg/acre (~KES 36,000/acre at KES 48/kg), but at Kirinyaga's 47/100 suitability a realistic target here is closer to 441 kg/acre (~KES 21,168/acre) unless the constraints above are addressed.