Growing Napier Grass in Tana River
Soil suitability analysis based on Tana River's nutrient profile
Tana River County is a challenging environment for Napier Grass (soil-match score 23/100) and will need significant amendment before planting. Local soils average pH 6.4 — slightly acidic to near-neutral and inside the 5–8 band Napier Grass prefers, so no lime is usually required. The main gap is potassium — measured at N 1.04 g/kg, P 8.5 mg/kg, K 108 mg/kg against this crop's medium/low/medium demand — so the fertilizer plan below prioritises closing that deficit. Napier Grass prefers loam soils, while Tana River is largely sandy, so drainage and organic-matter management matter more here. Tana River receives approximately 400 mm/year — well below Napier Grass's minimum of 800 mm — so supplemental irrigation would be essential for this crop. At current prices (about KES 5/kg) and a typical 15,000 kg/acre yield, a well-managed Napier Grass crop here can gross roughly KES 75,000 per acre.
Soil match analysis
| Nutrient | Tana River soil | Napier Grass needs | Status |
|---|---|---|---|
| pH | 6.4 | 5–8 | OK |
| Nitrogen | 1.04 g/kg | min 0.8 g/kg | OK |
| Phosphorus | 8.5 mg/kg | min 6 mg/kg | OK |
| Potassium | 108 mg/kg | min 150 mg/kg | Low |
Recommended seed varieties
Economics
Fertilizer prices
Green = subsidized · (Commercial) per 50kg bag