Growing Dolichos in Vihiga

Soil suitability analysis based on Vihiga's nutrient profile

Quick answer

Possible but challenging — Vihiga is only marginally suited to Dolichos. Vihiga's soil (pH 5.62, slightly acidic) gives Dolichos a suitability score of 52/100. Match fertilizer to Vihiga's nitrogen and phosphorus levels for the best result.

Dolichos can be grown in Vihiga County, but the soil scores 52/100 and needs targeted management to reach full potential. Local soils average pH 5.62 — slightly acidic to near-neutral and inside the 5–7.5 band Dolichos prefers, so no lime is usually required. Nitrogen (1.02 g/kg), phosphorus (14.8 mg/kg) and potassium (164 mg/kg) all meet Dolichos's requirements, so a maintenance fertilizer programme is enough. Dolichos prefers sandy loam soils, while Vihiga is largely clay loam, so drainage and organic-matter management matter more here. On ShambaIQ's soil-match model, Dolichos is the #65 soil match of the 106 crops we assess for Vihiga County. Dolichos's full potential is about 600 kg/acre (~KES 72,000/acre at KES 120/kg), but at Vihiga's 52/100 suitability a realistic target here is closer to 390 kg/acre (~KES 46,800/acre) unless the constraints above are addressed.

Better matched to Vihiga's soil: Sweet Potato, Soybeans, and Coffee (Arabica) — each scores higher on the same soil.

52Suitability score

Soil & climate match

FactorVihiga soilDolichos needsStatus
pH5.6257.5OK
Nitrogen1.02 g/kgmin 0.5 g/kgOK
Phosphorus14.8 mg/kgmin 6 mg/kgOK
Potassium164 mg/kgmin 100 mg/kgOK
Rainfall1,800 mm400–1,000 mmHigh
Altitude1,700 m1,000–2,100 mOK

Planting calendar

Long Rains

Month 1
Sowing & DAP Basal Fertilizer (NO CAN — nitrogen fixer)
Month 2
Weeding & Vine Support if needed
Month 3
Pod Fill & Harvesting

Short Rains

Month 1
Sowing & Basal Fertilizer (no CAN)
Month 2
Weeding & Pest Scouting
Month 3
Harvesting & Seed Drying

Dry Season

Month 1
Post-Harvest seed storage
Month 2
Land Resting (N benefit remains in soil)
Month 3
Seed Selection & preparation

Top dressing guide

Product
None
Timing
None required
Instruction
Dolichos (njahi) fixes its own nitrogen through rhizobia. Do NOT apply CAN — it suppresses nodulation and reduces yield. A starter dose of phosphorus at planting is enough.
Bags per Acre
0

Recommended seed varieties

Njahi BlackMedium/Highland
KALRO · 90-120 days · 8-12 bags/acre
Black hyacinth bean (njahi); popular in Central Kenya; high protein; nitrogen-fixing soil improver.
DL 1002Dryland/Medium
KALRO · 90-110 days · 7-11 bags/acre
Improved dual-purpose lablab; grain and fodder; tolerant to drought and low fertility.
Eldoret BrownMedium
KALRO · 100-130 days · 8-13 bags/acre
Brown-seeded selection; vigorous; good for intercropping with maize.
ELDO-KT Black 1Medium/Highland 10-2000m
University of Eldoret · 135-150 days · 14-22 bags/acre
Black seeded; short cooking time; uniform maturity.
ELDO-KT CreamMedium/Highland 10-2000m
University of Eldoret · 120-135 days · 16-25 bags/acre
Cream seeded; early maturity; good flavor; short cooking time.
ELDO-KT Black 2Medium/Highland 10-2000m
University of Eldoret · 120-135 days · 16-29 bags/acre
Black seeded; medium maturity; robust growth.

Economics

Market priceKES 120/kg
Expected yield in Vihiga390 kg/acre
Estimated revenueKES 46,800/acre
Adjusted for Vihiga's 52/100 suitability. Under ideal conditions Dolichos can reach 600 kg/acre (~KES 72,000/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(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