Growing African Nightshade in Kwale

Soil suitability analysis based on Kwale's nutrient profile

Quick answer

Generally not ideal — Kwale is poorly suited to African Nightshade. Kwale's soil (pH 6.76, near-neutral) gives African Nightshade a suitability score of 3/100. Match fertilizer to Kwale's nitrogen and phosphorus levels for the best result.

Kwale County is a challenging environment for African Nightshade (soil-match score 3/100) and will need significant amendment before planting. Local soils average pH 6.76 — neutral and inside the 5.5–7.5 band African Nightshade prefers, so no lime is usually required. The main gap is nitrogen, phosphorus, and potassium — measured at N 0.93 g/kg, P 9.8 mg/kg, K 131 mg/kg against this crop's high/medium/medium demand — so the fertilizer plan below prioritises closing those deficits. The county's predominantly sandy loam soils suit African Nightshade, which favours loam. At 200 m, the county sits below African Nightshade's preferred altitude range (1000–2200 m), which limits yield potential due to heat stress. On ShambaIQ's soil-match model, African Nightshade is the #84 soil match of the 106 crops we assess for Kwale County. African Nightshade's full potential is about 5,000 kg/acre (~KES 250,000/acre at KES 50/kg), but at Kwale's 3/100 suitability a realistic target here is closer to 188 kg/acre (~KES 9,400/acre) unless the constraints above are addressed.

Better matched to Kwale's soil: Dhania, Pigeon Peas, and Mango — each scores higher on the same soil.

3Suitability score

Soil & climate match

FactorKwale soilAfrican Nightshade needsStatus
pH6.765.5–7.5OK
Nitrogen0.93 g/kgmin 1.2 g/kgLow
Phosphorus9.8 mg/kgmin 12 mg/kgLow
Potassium131 mg/kgmin 150 mg/kgLow
Rainfall900 mm800–1,500 mmOK
Altitude200 m1,000–2,200 mLow

Planting calendar for Kwale

Long Rains· April–JuneMain season here

April
Transplanting & Basal Fertilizer (DAP)
May
First Harvest (leaf picking) & Top Dressing
June
Continuous Leaf Harvest

Short Rains· November–January

November
Transplanting & Basal Fertilizer
December
Weeding & Pest Control
January
Harvesting & Market

Dry Season· February–April

February
Irrigation & Continuous Harvesting
March
Top Dressing (CAN) every 2 weeks
April
Replanting if stand is old

Top dressing guide

Product
CAN
Timing
Week 2-3 after transplanting
Instruction
Top dress 2-3 weeks after transplanting and after each picking to push tender leaf regrowth
Bags per acre in Kwale
1.251

Kwale's nitrogen (0.93 g/kg) is 78% of the 1.2 g/kg African Nightshade needs, so the standard 1 bag/acre is raised to 1.25. Split it across two applications to limit leaching.

Recommended seed varieties

No variety in our list is specifically rated for Kwale's 200 m altitude and 900 mm rainfall, so all 3 are shown. Confirm with your agrovet before buying.

Managu KALROMedium/Highland
KALRO · 30-45 days · 2.5–4 tons/acre
Indigenous leafy vegetable; high iron and vitamin A; multiple harvests; very popular in Western Kenya.
Giant NightshadeMedium/Highland
Simlaw Seeds · 35-50 days · 2.8–4.3 tons/acre
Large-leaved selection; soft palatable leaves; high market demand.
OlevolosiMedium
KALRO · 30-45 days · 2.3–3.8 tons/acre
Broad-leaf type; slow bolting; continuous picking; drought tolerant.

Economics

Market priceKES 50/kg
Expected yield in Kwale188 kg/acre
Estimated revenueKES 9,400/acre
Adjusted for Kwale's 3/100 suitability. Under ideal conditions African Nightshade can reach 5,000 kg/acre (~KES 250,000/acre) — attainable here only after the climate and soil constraints below are addressed.

Preferred textureLoam

Fertilizer prices

DAP
KES 3,500(6,500)
CAN
KES 2,875(5,700)
NPK 17:17:17
KES 3,275(5,600)
Urea
KES 3,500(5,500)
Lime
KES 1,500(1,800)

Green = subsidized · (Commercial) per 50kg bag