Growing Potato in Tharaka Nithi
Soil suitability analysis based on Tharaka Nithi's nutrient profile
Tharaka Nithi County is well suited to Potato, scoring 83/100 on ShambaIQ's soil-match model. Local soils average pH 4.99 — strongly acidic and inside the 4.8–6.5 band Potato prefers, so no lime is usually required. The main gap is phosphorus — measured at N 1.23 g/kg, P 19.6 mg/kg, K 211 mg/kg against this crop's high/high/high demand — so the fertilizer plan below prioritises closing that deficit. The county's predominantly sandy loam soils suit Potato, which favours sandy loam. At current prices (about KES 32/kg) and a typical 4,000 kg/acre yield, a well-managed Potato crop here can gross roughly KES 128,000 per acre.
Suitability score
Soil match analysis
| Nutrient | Tharaka Nithi soil | Potato needs | Status |
|---|---|---|---|
| pH | 4.99 | 4.8–6.5 | OK |
| Nitrogen | 1.23 g/kg | min 1.2 g/kg | OK |
| Phosphorus | 19.6 mg/kg | min 20 mg/kg | Low |
| Potassium | 211 mg/kg | min 200 mg/kg | OK |
Planting calendar
Long Rains
Month 1
Planting Tubers & Basal Fertilizer (NPK)
Month 2
Earthing Up & Top Dressing (CAN)
Month 3
Pest Control (Blight) & Weeding
Short Rains
Month 1
Planting & Basal Fertilizer
Month 2
Earthing Up & Top Dressing
Month 3
Blight Control
Dry Season
Month 1
Harvesting & Storage
Month 2
Land Resting
Month 3
Seed Tuber Sprouting
Recommended seed varieties
ShangiMedium/Highland
KALRO · 80-90 days · 300-350 bags/acre
Very fast cooking; high tuber density per plant.
UnicaDryland/Medium
KALRO · 90-100 days · 350-400 bags/acre
Heat tolerant; highly resistant to late blight.
Economics
Market priceKES 32/kg
Expected yield4,000 kg/acre
Estimated revenueKES 128,000/acre
Preferred textureSandy Loam
Fertilizer prices
DAP
KES 2,500(6,500)
CAN
KES 2,500(4,500)
NPK 17:17:17
KES 2,500(5,600)
Urea
KES 2,500(5,500)
Lime
KES 1,500(1,800)
Green = subsidized · (Commercial) per 50kg bag