Growing Pyrethrum in Kirinyaga

Soil suitability analysis based on Kirinyaga's nutrient profile

Pyrethrum can be grown in Kirinyaga County, but the soil scores 58/100 and needs targeted management to reach full potential. Local soils average pH 5.31 — moderately acidic and inside the 5–6.5 band Pyrethrum prefers, so no lime is usually required. The main gap is phosphorus — measured at N 1.36 g/kg, P 12.5 mg/kg, K 177 mg/kg against this crop's medium/high/medium demand — so the fertilizer plan below prioritises closing that deficit. Pyrethrum prefers loam soils, while Kirinyaga is largely clay, so drainage and organic-matter management matter more here. Pyrethrum's full potential is about 500 kg/acre (~KES 140,000/acre at KES 280/kg), but at Kirinyaga's 58/100 suitability a realistic target here is closer to 363 kg/acre (~KES 101,640/acre) unless the constraints above are addressed.