Growing Yams in Nairobi

Soil suitability analysis based on Nairobi's nutrient profile

Quick answer

Possible but challenging — Nairobi is only marginally suited to Yams. Nairobi's soil (pH 6.85, near-neutral) gives Yams a suitability score of 46/100. Match fertilizer to Nairobi's nitrogen and phosphorus levels for the best result.

Yams can be grown in Nairobi County, but the soil scores 46/100 and needs targeted management to reach full potential. At an average pH of 6.85 the soil sits above Yams's preferred 5.5–6.5 range, which can limit uptake of phosphorus and micronutrients. Nitrogen (1.1 g/kg), phosphorus (22.1 mg/kg) and potassium (236 mg/kg) all meet Yams's requirements, so a maintenance fertilizer programme is enough. Yams prefers sandy loam soils, while Nairobi is largely clay loam, so drainage and organic-matter management matter more here. On ShambaIQ's soil-match model, Yams is the #98 soil match of the 106 crops we assess for Nairobi County. Yams's full potential is about 7,000 kg/acre (~KES 560,000/acre at KES 80/kg), but at Nairobi's 46/100 suitability a realistic target here is closer to 4,025 kg/acre (~KES 322,000/acre) unless the constraints above are addressed.

Better matched to Nairobi's soil: Dhania, Pumpkin, and Rosemary — each scores higher on the same soil.

46Suitability score

Soil & climate match

FactorNairobi soilYams needsStatus
pH6.855.56.5Adjust
Nitrogen1.1 g/kgmin 0.8 g/kgOK
Phosphorus22.1 mg/kgmin 12 mg/kgOK
Potassium236 mg/kgmin 200 mg/kgOK
Rainfall900 mm1,200–1,800 mmLow
Altitude1,700 m0–1,800 mOK

Recommended seed varieties

Local White (Nyandarua/Meru)Medium/Highland 1000-1800m
Local · 240-300 days · 2.5–3.5 tons/acre
Traditional tuber crop; highly valued for food security; propagated via tuber sets.
Local PurpleMedium/Highland 1000-1800m
Local · 270-330 days · 2–3 tons/acre
Vigorous climbing vine; highly nutritious tuber.

Economics

Market priceKES 80/kg
Expected yield in Nairobi4,025 kg/acre
Estimated revenueKES 322,000/acre
Adjusted for Nairobi's 46/100 suitability. Under ideal conditions Yams can reach 7,000 kg/acre (~KES 560,000/acre) — attainable here only after the climate and soil constraints below are addressed.

Preferred textureSandy Loam

Fertilizer prices

DAP
KES 3,500(6,500)
CAN
KES 2,875(5,700)
NPK 17:17:17
KES 3,275(5,600)
Urea
KES 3,500(5,500)
Lime
KES 1,500(1,800)

Green = subsidized · (Commercial) per 50kg bag