Growing Sweet Potato in Machakos

Soil suitability analysis based on Machakos's nutrient profile

Quick answer

Yes, with the right inputs — Machakos is moderately suited to Sweet Potato. Machakos's soil (pH 7.03, near-neutral) gives Sweet Potato a suitability score of 71/100. Match fertilizer to Machakos's nitrogen and phosphorus levels for the best result.

Machakos County is a solid choice for Sweet Potato, with a soil-match score of 71/100. At an average pH of 7.03 the soil sits above Sweet Potato's preferred 4.5–7 range, which can limit uptake of phosphorus and micronutrients. Nitrogen (0.82 g/kg), phosphorus (31.4 mg/kg) and potassium (338 mg/kg) all meet Sweet Potato's requirements, so a maintenance fertilizer programme is enough. The county's predominantly sandy loam soils suit Sweet Potato, which favours sandy loam. On ShambaIQ's soil-match model, Sweet Potato is the #68 soil match of the 106 crops we assess for Machakos County. Sweet Potato's full potential is about 5,000 kg/acre (~KES 90,000/acre at KES 18/kg), but at Machakos's 71/100 suitability a realistic target here is closer to 4,438 kg/acre (~KES 79,884/acre) unless the constraints above are addressed.

71Suitability score

Soil & climate match

FactorMachakos soilSweet Potato needsStatus
pH7.034.57Adjust
Nitrogen0.82 g/kgmin 0.5 g/kgOK
Phosphorus31.4 mg/kgmin 12 mg/kgOK
Potassium338 mg/kgmin 200 mg/kgOK
Rainfall700 mm600–1,800 mmOK
Altitude1,100 m0–2,200 mOK

Planting calendar for Machakos

Long Rains· MarchMay

March
Vine Cutting Planting & Basal Fertilizer
April
Weeding & Vine Management
May
Harvesting & Storage

Short Rains· OctoberDecemberMain season here

October
Vine Planting & Basal Fertilizer
November
Vine Trailing & Weeding
December
Harvesting

Dry Season· JanuaryMarch

January
Irrigation & Vine Planting
February
Weeding
March
Harvesting & Vine Multiplication

Top dressing guide

Product
None
Timing
None required
Instruction
Sweet potatoes rarely need top dressing. Excess N promotes vines over tubers.
Bags per acre in Machakos
0

Machakos's nitrogen reads 0.82 g/kg, but the rate stays at zero: Sweet Potato is not top-dressed, for the crop-specific reason above.

Seed varieties for Machakos

Varieties suited to Machakos's 1,100 m altitude and 700 mm annual rainfall — 1 of 5 sweet potato varieties we list.

KabodeMedium/Dryland
CIP/KALRO · 120-150 days · 3–4 tons/acre
Orange-fleshed; high Vitamin A; drought tolerant.

Economics

Market priceKES 18/kg
Expected yield in Machakos4,438 kg/acre
Estimated revenueKES 79,884/acre
Adjusted for Machakos's 71/100 suitability. Under ideal conditions Sweet Potato can reach 5,000 kg/acre (~KES 90,000/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