Growing Green Grams in Mandera

Soil suitability analysis based on Mandera's nutrient profile

Quick answer

Generally not ideal — Mandera is poorly suited to Green Grams. Mandera's soil (pH 8.38, alkaline) gives Green Grams a suitability score of 30/100. Match fertilizer to Mandera's nitrogen and phosphorus levels for the best result.

Mandera County is a challenging environment for Green Grams (soil-match score 30/100) and will need significant amendment before planting. At an average pH of 8.38 the soil sits above Green Grams's preferred 5.5–8 range, which can limit uptake of phosphorus and micronutrients. Nitrogen (0.53 g/kg), phosphorus (38.3 mg/kg) and potassium (420 mg/kg) all meet Green Grams's requirements, so a maintenance fertilizer programme is enough. The county's predominantly sandy soils suit Green Grams, which favours sandy loam. Mandera receives approximately 180 mm/year — well below Green Grams's minimum of 250 mm — so supplemental irrigation would be essential for this crop. Green Grams's full potential is about 400 kg/acre (~KES 48,000/acre at KES 120/kg), but at Mandera's 30/100 suitability a realistic target here is closer to 150 kg/acre (~KES 18,000/acre) unless the constraints above are addressed.

30Suitability score

Soil & climate match

FactorMandera soilGreen Grams needsStatus
pH8.385.58Adjust
Nitrogen0.53 g/kgmin 0.5 g/kgOK
Phosphorus38.3 mg/kgmin 6 mg/kgOK
Potassium420 mg/kgmin 100 mg/kgOK
Rainfall180 mm250–700 mmLow
Altitude250 m0–1,800 mOK

Top dressing guide

Product
None
Timing
None required
Instruction
Green Grams fix atmospheric Nitrogen. No top dressing needed. Inoculate seed with Rhizobium before planting.
Bags per Acre
0

Recommended seed varieties

N26Dryland/Medium
KALRO · 60-65 days · 3-5 bags/acre
Early maturing; tolerant to drought; popular in eastern Kenya.
KS 20Medium
KALRO · 65-75 days · 4-6 bags/acre
High yielding; good seed quality; resistant to yellow mosaic virus.

Economics

Market priceKES 120/kg
Expected yield in Mandera150 kg/acre
Estimated revenueKES 18,000/acre
Adjusted for Mandera's 30/100 suitability. Under ideal conditions Green Grams can reach 400 kg/acre (~KES 48,000/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(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