Growing Rosemary in Turkana

Soil suitability analysis based on Turkana's nutrient profile

Turkana County is a challenging environment for Rosemary (soil-match score 9/100) and will need significant amendment before planting. Local soils average pH 7.95 — alkaline and inside the 6–8 band Rosemary prefers, so no lime is usually required. The main gap is nitrogen — measured at N 0.41 g/kg, P 38.5 mg/kg, K 417 mg/kg against this crop's medium/medium/medium demand — so the fertilizer plan below prioritises closing that deficit. The county's predominantly sandy soils suit Rosemary, which favours sandy loam. At 400 m, the county sits below Rosemary's preferred altitude range (800–2400 m), which limits yield potential due to heat stress. Rosemary's full potential is about 2,500 kg/acre (~KES 375,000/acre at KES 150/kg), but at Turkana's 9/100 suitability a realistic target here is closer to 281 kg/acre (~KES 42,150/acre) unless the constraints above are addressed.