Growing Yams in Isiolo

Soil suitability analysis based on Isiolo's nutrient profile

Isiolo County is a challenging environment for Yams (soil-match score 4/100) and will need significant amendment before planting. At an average pH of 7.83 the soil sits above Yams's preferred 5.5–6.5 range, which can limit uptake of phosphorus and micronutrients. The main gap is nitrogen — measured at N 0.46 g/kg, P 37.4 mg/kg, K 395 mg/kg against this crop's medium/medium/high demand — so the fertilizer plan below prioritises closing that deficit. The county's predominantly sandy soils suit Yams, which favours sandy loam. Isiolo receives approximately 350 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.