Growing Grapes in Siaya

Soil suitability analysis based on Siaya's nutrient profile

Quick answer

Possible but challenging — Siaya is only marginally suited to Grapes. Siaya's soil (pH 5.33, strongly acidic) gives Grapes a suitability score of 54/100. Apply agricultural lime before planting to unlock phosphorus and lift the score.

Grapes can be grown in Siaya County, but the soil scores 54/100 and needs targeted management to reach full potential. At an average pH of 5.33 the soil is moderately acidic, below Grapes's preferred 6–7.5 range; agricultural lime will lift pH and unlock phosphorus the crop cannot otherwise access. The main gap is phosphorus and potassium — measured at N 1.2 g/kg, P 12.1 mg/kg, K 134 mg/kg against this crop's medium/high/high demand — so the fertilizer plan below prioritises closing those deficits. The county's predominantly clay loam soils suit Grapes, which favours loam. On ShambaIQ's soil-match model, Grapes is the #77 soil match of the 106 crops we assess for Siaya County. Grapes's full potential is about 8,000 kg/acre (~KES 1,200,000/acre at KES 150/kg), but at Siaya's 54/100 suitability a realistic target here is closer to 5,400 kg/acre (~KES 810,000/acre) unless the constraints above are addressed.

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

54Suitability score

Soil & climate match

FactorSiaya soilGrapes needsStatus
pH5.3367.5Adjust
Nitrogen1.2 g/kgmin 0.8 g/kgOK
Phosphorus12.1 mg/kgmin 20 mg/kgLow
Potassium134 mg/kgmin 200 mg/kgLow
Rainfall1,200 mm500–1,000 mmHigh
Altitude1,200 m0–1,800 mOK

Planting calendar for Siaya

Long Rains· MarchMayMain season here

March
Pruning & Bud Break & Basal
April
Training & Top Dressing
May
Fruit Set & Harvest

Short Rains· SeptemberNovember

September
Pruning & Bud Break
October
Training & Top Dressing
November
Fruit Set & Harvest

Top dressing guide

Product
CAN
Timing
At bud break and fruit set
Instruction
Add potassium at veraison for sugar and colour. Avoid late nitrogen.
Bags per acre in Siaya
0.5

Siaya's nitrogen (1.2 g/kg) already meets Grapes's 0.8 g/kg requirement, so this is a maintenance rate.

Economics

Market priceKES 150/kg
Expected yield in Siaya5,400 kg/acre
Estimated revenueKES 810,000/acre
Adjusted for Siaya's 54/100 suitability. Under ideal conditions Grapes can reach 8,000 kg/acre (~KES 1,200,000/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