Growing Sunflower in Vihiga

Soil suitability analysis based on Vihiga's nutrient profile

Vihiga County is a challenging environment for Sunflower (soil-match score 37/100) and will need significant amendment before planting. At an average pH of 5.62 the soil is slightly acidic to near-neutral, below Sunflower's preferred 6–7.5 range; agricultural lime will lift pH and unlock phosphorus the crop cannot otherwise access. Nitrogen (1.02 g/kg), phosphorus (14.8 mg/kg) and potassium (164 mg/kg) all meet Sunflower's requirements, so a maintenance fertilizer programme is enough. Sunflower prefers sandy soils, while Vihiga is largely clay loam, 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 Vihiga's 37/100 suitability a realistic target here is closer to 347 kg/acre (~KES 16,656/acre) unless the constraints above are addressed.