Growing Onion in Kisii
Soil suitability analysis based on Kisii's nutrient profile
Possible but challenging — Kisii is only marginally suited to Onion. Kisii's soil (pH 5.21, strongly acidic) gives Onion a suitability score of 48/100. Apply agricultural lime before planting to unlock phosphorus and lift the score.
Onion can be grown in Kisii County, but the soil scores 48/100 and needs targeted management to reach full potential. At an average pH of 5.21 the soil is moderately acidic, below Onion's preferred 6–7 range; agricultural lime will lift pH and unlock phosphorus the crop cannot otherwise access. The main gap is nitrogen and phosphorus — measured at N 1.09 g/kg, P 13.1 mg/kg, K 151 mg/kg against this crop's high/high/medium demand — so the fertilizer plan below prioritises closing those deficits. Onion prefers sandy loam soils, while Kisii is largely clay loam, so drainage and organic-matter management matter more here. On ShambaIQ's soil-match model, Onion is the #72 soil match of the 106 crops we assess for Kisii County. Onion's full potential is about 6,000 kg/acre (~KES 420,000/acre at KES 70/kg), but at Kisii's 48/100 suitability a realistic target here is closer to 3,600 kg/acre (~KES 252,000/acre) unless the constraints above are addressed.
Better matched to Kisii's soil: Tea, Macadamia, and Pineapple — each scores higher on the same soil.
Soil & climate match
| Factor | Kisii soil | Onion needs | Status |
|---|---|---|---|
| pH | 5.21 | 6–7 | Adjust |
| Nitrogen | 1.09 g/kg | min 1.2 g/kg | Low |
| Phosphorus | 13.1 mg/kg | min 20 mg/kg | Low |
| Potassium | 151 mg/kg | min 150 mg/kg | OK |
| Rainfall | 1,500 mm | 500–1,000 mm | High |
| Altitude | 1,700 m | 0–2,000 m | OK |
Planting calendar for Kisii
Long Rains· March–MayMain season here
Short Rains· August–October
Dry Season· January–March
Top dressing guide
Kisii's nitrogen (1.09 g/kg) is 91% of the 1.2 g/kg Onion needs, so the standard 0.5 bags/acre is raised to 0.75. Split it across two applications to limit leaching.
Seed varieties for Kisii
Varieties suited to Kisii's 1,700 m altitude and 1,500 mm annual rainfall — 2 of 2 onion varieties we list.
Economics
Fertilizer prices
Green = subsidized · (Commercial) per 50kg bag