Growing Dolichos in Isiolo

Soil suitability analysis based on Isiolo's nutrient profile

Quick answer

Generally not ideal — Isiolo is poorly suited to Dolichos. Isiolo's soil (pH 7.83, alkaline) gives Dolichos a suitability score of 39/100. Match fertilizer to Isiolo's nitrogen and phosphorus levels for the best result.

Isiolo County is a challenging environment for Dolichos (soil-match score 39/100) and will need significant amendment before planting. At an average pH of 7.83 the soil sits above Dolichos's preferred 5–7.5 range, which can limit uptake of phosphorus and micronutrients. The main gap is nitrogen — measured at N 0.46 g/kg, P 37.4 mg/kg, K 395 mg/kg against this crop's low/low/low demand — so the fertilizer plan below prioritises closing that deficit. The county's predominantly sandy soils suit Dolichos, which favours sandy loam. On ShambaIQ's soil-match model, Dolichos is the #19 soil match of the 106 crops we assess for Isiolo County. Dolichos's full potential is about 600 kg/acre (~KES 72,000/acre at KES 120/kg), but at Isiolo's 39/100 suitability a realistic target here is closer to 293 kg/acre (~KES 35,160/acre) unless the constraints above are addressed.

Better matched to Isiolo's soil: Sisal, Aloe Vera, and Green Grams — each scores higher on the same soil.

39Suitability score

Soil & climate match

FactorIsiolo soilDolichos needsStatus
pH7.8357.5Adjust
Nitrogen0.46 g/kgmin 0.5 g/kgLow
Phosphorus37.4 mg/kgmin 6 mg/kgOK
Potassium395 mg/kgmin 100 mg/kgOK
Rainfall350 mm400–1,000 mmLow
Altitude900 m1,000–2,100 mLow

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 Isiolo293 kg/acre
Estimated revenueKES 35,160/acre
Adjusted for Isiolo's 39/100 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