Growing Rosemary in Vihiga
Soil suitability analysis based on Vihiga's nutrient profile
Generally not ideal — Vihiga is poorly suited to Rosemary. Vihiga's soil (pH 5.62, slightly acidic) gives Rosemary a suitability score of 35/100. Match fertilizer to Vihiga's nitrogen and phosphorus levels for the best result.
Vihiga County is a challenging environment for Rosemary (soil-match score 35/100) and will need significant amendment before planting. At an average pH of 5.62 the soil is slightly acidic to near-neutral, below Rosemary's preferred 6–8 range; agricultural lime will lift pH and unlock phosphorus the crop cannot otherwise access. Nitrogen (1.02 g/kg), phosphorus (14.8 mg/kg) and potassium (164 mg/kg) all meet Rosemary's requirements, so a maintenance fertilizer programme is enough. Rosemary prefers sandy loam soils, while Vihiga is largely clay loam, so drainage and organic-matter management matter more here. On ShambaIQ's soil-match model, Rosemary is the #92 soil match of the 106 crops we assess for Vihiga County. Rosemary's full potential is about 2,500 kg/acre (~KES 375,000/acre at KES 150/kg), but at Vihiga's 35/100 suitability a realistic target here is closer to 1,094 kg/acre (~KES 164,100/acre) unless the constraints above are addressed.
Better matched to Vihiga's soil: Sweet Potato, Soybeans, and Coffee (Arabica) — each scores higher on the same soil.
Soil & climate match
| Factor | Vihiga soil | Rosemary needs | Status |
|---|---|---|---|
| pH | 5.62 | 6–8 | Adjust |
| Nitrogen | 1.02 g/kg | min 0.8 g/kg | OK |
| Phosphorus | 14.8 mg/kg | min 12 mg/kg | OK |
| Potassium | 164 mg/kg | min 150 mg/kg | OK |
| Rainfall | 1,800 mm | 400–900 mm | High |
| Altitude | 1,700 m | 800–2,400 m | OK |
Planting calendar for Vihiga
Long Rains· March–MayMain season here
Short Rains· August–October
Top dressing guide
Vihiga's nitrogen (1.02 g/kg) already meets Rosemary's 0.8 g/kg requirement, so this is a maintenance rate.
Economics
Fertilizer prices
Green = subsidized · (Commercial) per 50kg bag