Growing French Beans in Kiambu

Soil suitability analysis based on Kiambu's nutrient profile

Quick answer

Yes, with the right inputs — Kiambu is moderately suited to French Beans. Kiambu's soil (pH 5.28, strongly acidic) gives French Beans a suitability score of 71/100. Apply agricultural lime before planting to unlock phosphorus and lift the score.

Kiambu County is a solid choice for French Beans, with a soil-match score of 71/100. At an average pH of 5.28 the soil is moderately acidic, below French Beans's preferred 5.8–7 range; agricultural lime will lift pH and unlock phosphorus the crop cannot otherwise access. The main gap is phosphorus — measured at N 1.01 g/kg, P 13.7 mg/kg, K 169 mg/kg against this crop's low/high/medium demand — so the fertilizer plan below prioritises closing that deficit. French Beans prefers loam soils, while Kiambu is largely clay, so drainage and organic-matter management matter more here. On ShambaIQ's soil-match model, French Beans is the #33 soil match of the 106 crops we assess for Kiambu County. French Beans's full potential is about 3,500 kg/acre (~KES 280,000/acre at KES 80/kg), but at Kiambu's 71/100 suitability a realistic target here is closer to 3,106 kg/acre (~KES 248,480/acre) unless the constraints above are addressed.

71Suitability score

Soil & climate match

FactorKiambu soilFrench Beans needsStatus
pH5.285.8–7Adjust
Nitrogen1.01 g/kgmin 0.5 g/kgOK
Phosphorus13.7 mg/kgmin 20 mg/kgLow
Potassium169 mg/kgmin 150 mg/kgOK
Rainfall1,100 mm900–1,500 mmOK
Altitude1,700 m1,000–2,100 mOK

Planting calendar for Kiambu

Long Rains· March–MayMain season here

March
Sowing & DAP Basal Fertilizer (at planting)
April
Weeding & Pest Scouting (bean fly)
May
Pod Fill & Harvesting starts

Short Rains· October–December

October
Sowing & Basal Fertilizer
November
Weeding & Bean Fly Control
December
Harvesting & Grading for export

Dry Season· January–March

January
Harvesting remaining pods & Land Preparation
February
Soil pH testing & lime if needed
March
Seed multiplication & storage

Top dressing guide

Product
CAN
Timing
Week 2-3 after emergence
Instruction
Apply when seedlings have 2-3 true leaves, then a second light dose at flowering for pod fill
Bags per acre in Kiambu
1

Kiambu's nitrogen (1.01 g/kg) already meets French Beans's 0.5 g/kg requirement, so this is a maintenance rate.

Seed varieties for Kiambu

5 french beans varieties are rated for Kiambu's altitude (1,700 m) and rainfall (1,100 mm):

Julia· Medium/HighlandSamantha· Medium/HighlandAmy· Medium/HighlandSerengeti· Medium/HighlandTeresa· Medium/Highland
Full variety details — maturity, yield & breeder →

Economics

Market priceKES 80/kg
Expected yield in Kiambu3,106 kg/acre
Estimated revenueKES 248,480/acre
Adjusted for Kiambu's 71/100 suitability. Under ideal conditions French Beans can reach 3,500 kg/acre (~KES 280,000/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