Growing Cotton in Kirinyaga

Soil suitability analysis based on Kirinyaga's nutrient profile

Kirinyaga County is a solid choice for Cotton, with a soil-match score of 63/100. At an average pH of 5.31 the soil is moderately acidic, below Cotton's preferred 5.8–8 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 Cotton's requirements, so a maintenance fertilizer programme is enough. The county's predominantly clay soils suit Cotton, which favours clay. Cotton's full potential is about 900 kg/acre (~KES 61,200/acre at KES 68/kg), but at Kirinyaga's 63/100 suitability a realistic target here is closer to 709 kg/acre (~KES 48,212/acre) unless the constraints above are addressed.

63Suitability score

Soil & climate match

FactorKirinyaga soilCotton needsStatus
pH5.315.88Adjust
Nitrogen1.36 g/kgmin 0.8 g/kgOK
Phosphorus12.5 mg/kgmin 12 mg/kgOK
Potassium177 mg/kgmin 150 mg/kgOK
Rainfall1,300 mm450–1,200 mmHigh
Altitude1,500 m0–1,500 mOK

Top dressing guide

Product
CAN
Timing
Week 4–6 after emergence
Instruction
Apply at squaring stage for boll development.
Bags per Acre
0.5

Recommended seed varieties

KSA 81MDryland/Medium
KALRO · 150-180 days · 10-15 bags/acre
Medium staple; adapted to western Kenya conditions.
HART 89MDryland
KALRO · 140-170 days · 8-12 bags/acre
Good lint quality; tolerant to bacterial blight.

Economics

Market priceKES 68/kg
Expected yield in Kirinyaga709 kg/acre
Estimated revenueKES 48,212/acre
Adjusted for Kirinyaga's 63/100 suitability. Under ideal conditions Cotton can reach 900 kg/acre (~KES 61,200/acre) — attainable here only after the climate and soil constraints below are addressed.

Preferred textureClay

Fertilizer prices

DAP
KES 3,500(6,500)
CAN
KES 2,875(4,500)
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