Growing Yams in Makueni

Soil suitability analysis based on Makueni's nutrient profile

Makueni County is a challenging environment for Yams (soil-match score 16/100) and will need significant amendment before planting. At an average pH of 7.5 the soil sits above Yams's preferred 5.5–6.5 range, which can limit uptake of phosphorus and micronutrients. Nitrogen (0.86 g/kg), phosphorus (29.6 mg/kg) and potassium (351 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. Makueni receives approximately 600 mm/year — well below Yams's minimum of 1200 mm — so supplemental irrigation would be essential for this crop. 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.