Growing Yams in Tharaka Nithi

Soil suitability analysis based on Tharaka Nithi's nutrient profile

Tharaka Nithi County is a challenging environment for Yams (soil-match score 44/100) and will need significant amendment before planting. At an average pH of 4.99 the soil is strongly acidic, below Yams's preferred 5.5–6.5 range; agricultural lime will lift pH and unlock phosphorus the crop cannot otherwise access. Nitrogen (1.23 g/kg), phosphorus (19.6 mg/kg) and potassium (211 mg/kg) all meet Yams's requirements, so a maintenance fertilizer programme is enough. The county's predominantly sandy loam soils suit Yams, which favours sandy loam. At current prices (about KES 80/kg) and a typical 6,000 kg/acre yield, a well-managed Yams crop here can gross roughly KES 480,000 per acre.