Growing Oilseed Rape (Canola) in Kirinyaga

Soil suitability analysis based on Kirinyaga's nutrient profile

Quick answer

Possible but challenging — Kirinyaga is only marginally suited to Oilseed Rape (Canola). Kirinyaga's soil (pH 5.31, strongly acidic) gives Oilseed Rape (Canola) a suitability score of 50/100. Apply agricultural lime before planting to unlock phosphorus and lift the score.

Oilseed Rape (Canola) can be grown in Kirinyaga County, but the soil scores 50/100 and needs targeted management to reach full potential. At an average pH of 5.31 the soil is moderately acidic, below Oilseed Rape (Canola)'s preferred 5.8–7.5 range; agricultural lime will lift pH and unlock phosphorus the crop cannot otherwise access. 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 high/high/medium demand — so the fertilizer plan below prioritises closing that deficit. Oilseed Rape (Canola) prefers loam soils, while Kirinyaga is largely clay, so drainage and organic-matter management matter more here. On ShambaIQ's soil-match model, Oilseed Rape (Canola) is the #81 soil match of the 106 crops we assess for Kirinyaga County. Oilseed Rape (Canola)'s full potential is about 1,000 kg/acre (~KES 60,000/acre at KES 60/kg), but at Kirinyaga's 50/100 suitability a realistic target here is closer to 625 kg/acre (~KES 37,500/acre) unless the constraints above are addressed.

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

50Suitability score

Soil & climate match

FactorKirinyaga soilOilseed Rape (Canola) needsStatus
pH5.315.87.5Adjust
Nitrogen1.36 g/kgmin 1.2 g/kgOK
Phosphorus12.5 mg/kgmin 20 mg/kgLow
Potassium177 mg/kgmin 150 mg/kgOK
Rainfall1,300 mm400–900 mmHigh
Altitude1,500 m1,500–2,800 mOK

Planting calendar for Kirinyaga

Long Rains· MarchMayMain season here

March
Land Prep & Sowing & Basal
April
Top Dressing & Weeding
May
Flowering & Pod Fill & Harvest

Short Rains· OctoberDecember

October
Land Prep & Sowing & Basal
November
Top Dressing & Weeding
December
Flowering & Pod Fill & Harvest

Top dressing guide

Product
CAN
Timing
Week 4 and at stem elongation
Instruction
Sulfur-demanding — prefer Ammonium Sulphate. Add boron at flowering for pod set.
Bags per acre in Kirinyaga
0.5

Kirinyaga's nitrogen (1.36 g/kg) already meets Oilseed Rape (Canola)'s 1.2 g/kg requirement, so this is a maintenance rate.

Economics

Market priceKES 60/kg
Expected yield in Kirinyaga625 kg/acre
Estimated revenueKES 37,500/acre
Adjusted for Kirinyaga's 50/100 suitability. Under ideal conditions Oilseed Rape (Canola) can reach 1,000 kg/acre (~KES 60,000/acre) — attainable here only after the climate and soil constraints below are addressed.

Preferred textureLoam

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