Growing Sweet Potato in Mandera
Soil suitability analysis based on Mandera's nutrient profile
Generally not ideal — Mandera is poorly suited to Sweet Potato. Mandera's soil (pH 8.38, alkaline) gives Sweet Potato a suitability score of 4/100. Match fertilizer to Mandera's nitrogen and phosphorus levels for the best result.
Mandera County is a challenging environment for Sweet Potato (soil-match score 4/100) and will need significant amendment before planting. At an average pH of 8.38 the soil sits above Sweet Potato's preferred 4.5–7 range, which can limit uptake of phosphorus and micronutrients. Nitrogen (0.53 g/kg), phosphorus (38.3 mg/kg) and potassium (420 mg/kg) all meet Sweet Potato's requirements, so a maintenance fertilizer programme is enough. The county's predominantly sandy soils suit Sweet Potato, which favours sandy loam. Mandera receives approximately 180 mm/year — well below Sweet Potato's minimum of 600 mm — so supplemental irrigation would be essential for this crop. On ShambaIQ's soil-match model, Sweet Potato is the #39 soil match of the 106 crops we assess for Mandera County. Sweet Potato's full potential is about 5,000 kg/acre (~KES 90,000/acre at KES 18/kg), but at Mandera's 4/100 suitability a realistic target here is closer to 250 kg/acre (~KES 4,500/acre) unless the constraints above are addressed.
Better matched to Mandera's soil: Sisal, Aloe Vera, and Green Grams — each scores higher on the same soil.
Soil & climate match
| Factor | Mandera soil | Sweet Potato needs | Status |
|---|---|---|---|
| pH | 8.38 | 4.5–7 | Adjust |
| Nitrogen | 0.53 g/kg | min 0.5 g/kg | OK |
| Phosphorus | 38.3 mg/kg | min 12 mg/kg | OK |
| Potassium | 420 mg/kg | min 200 mg/kg | OK |
| Rainfall | 180 mm | 600–1,800 mm | Low |
| Altitude | 250 m | 0–2,200 m | OK |
Planting calendar
Long Rains
Short Rains
Dry Season
Top dressing guide
Recommended seed varieties
Economics
Fertilizer prices
Green = subsidized · (Commercial) per 50kg bag