Growing Cowpeas in Kirinyaga
Soil suitability analysis based on Kirinyaga's nutrient profile
Possible but challenging — Kirinyaga is only marginally suited to Cowpeas. Kirinyaga's soil (pH 5.31, strongly acidic) gives Cowpeas a suitability score of 43/100. Apply agricultural lime before planting to unlock phosphorus and lift the score.
Kirinyaga County is a challenging environment for Cowpeas (soil-match score 43/100) and will need significant amendment before planting. Local soils average pH 5.31 — moderately acidic and inside the 5–8 band Cowpeas prefers, so no lime is usually required. Nitrogen (1.36 g/kg), phosphorus (12.5 mg/kg) and potassium (177 mg/kg) all meet Cowpeas's requirements, so a maintenance fertilizer programme is enough. Cowpeas prefers sandy soils, while Kirinyaga is largely clay, so drainage and organic-matter management matter more here. On ShambaIQ's soil-match model, Cowpeas is the #89 soil match of the 106 crops we assess for Kirinyaga County. Cowpeas's full potential is about 450 kg/acre (~KES 29,250/acre at KES 65/kg), but at Kirinyaga's 43/100 suitability a realistic target here is closer to 242 kg/acre (~KES 15,730/acre) unless the constraints above are addressed.
Better matched to Kirinyaga's soil: Tea, Macadamia, and Pineapple — each scores higher on the same soil.
Soil & climate match
| Factor | Kirinyaga soil | Cowpeas needs | Status |
|---|---|---|---|
| pH | 5.31 | 5–8 | OK |
| Nitrogen | 1.36 g/kg | min 0.5 g/kg | OK |
| Phosphorus | 12.5 mg/kg | min 6 mg/kg | OK |
| Potassium | 177 mg/kg | min 100 mg/kg | OK |
| Rainfall | 1,300 mm | 250–700 mm | High |
| Altitude | 1,500 m | 0–1,800 m | OK |
Top dressing guide
Kirinyaga's nitrogen reads 1.36 g/kg, but the rate stays at zero: Cowpeas is not top-dressed, for the crop-specific reason above.
Seed varieties for Kirinyaga
Varieties suited to Kirinyaga's 1,500 m altitude and 1,300 mm annual rainfall — 1 of 2 cowpeas varieties we list.
Economics
Fertilizer prices
Green = subsidized · (Commercial) per 50kg bag