Growing Sesame (Simsim) in Kirinyaga

Soil suitability analysis based on Kirinyaga's nutrient profile

Quick answer

Yes, with the right inputs — Kirinyaga is moderately suited to Sesame (Simsim). Kirinyaga's soil (pH 5.31, strongly acidic) gives Sesame (Simsim) a suitability score of 55/100. Apply agricultural lime before planting to unlock phosphorus and lift the score.

Sesame (Simsim) can be grown in Kirinyaga County, but the soil scores 55/100 and needs targeted management to reach full potential. At an average pH of 5.31 the soil is moderately acidic, below Sesame (Simsim)'s preferred 5.5–7 range; agricultural lime will lift pH and unlock phosphorus the crop cannot otherwise access. Nitrogen (1.36 g/kg), phosphorus (12.5 mg/kg) and potassium (177 mg/kg) all meet Sesame (Simsim)'s requirements, so a maintenance fertilizer programme is enough. Sesame (Simsim) prefers sandy soils, while Kirinyaga is largely clay, so drainage and organic-matter management matter more here. On ShambaIQ's soil-match model, Sesame (Simsim) is the #75 soil match of the 106 crops we assess for Kirinyaga County. Sesame (Simsim)'s full potential is about 250 kg/acre (~KES 87,500/acre at KES 350/kg), but at Kirinyaga's 55/100 suitability a realistic target here is closer to 172 kg/acre (~KES 60,200/acre) unless the constraints above are addressed.

Better matched to Kirinyaga's soil: Tea, Macadamia, and Pineapple — each scores higher on the same soil.

55Suitability score

Soil & climate match

FactorKirinyaga soilSesame (Simsim) needsStatus
pH5.315.57Adjust
Nitrogen1.36 g/kgmin 0.5 g/kgOK
Phosphorus12.5 mg/kgmin 6 mg/kgOK
Potassium177 mg/kgmin 100 mg/kgOK
Rainfall1,300 mm300–800 mmHigh
Altitude1,500 m0–1,600 mOK

Recommended seed varieties

KSS-6 (KS-S6)Lowland 200-1000m
Kenya Seed Company · 75 days · 7-9 bags/acre
Highly aromatic white seeds; high podding ability; rust & shootfly tolerant.

Economics

Market priceKES 350/kg
Expected yield in Kirinyaga172 kg/acre
Estimated revenueKES 60,200/acre
Adjusted for Kirinyaga's 55/100 suitability. Under ideal conditions Sesame (Simsim) can reach 250 kg/acre (~KES 87,500/acre) — attainable here only after the climate and soil constraints below are addressed.

Preferred textureSandy

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