Growing Sunflower in Nyandarua

Soil suitability analysis based on Nyandarua's nutrient profile

Quick answer

Possible but challenging — Nyandarua is only marginally suited to Sunflower. Nyandarua's soil (pH 5.38, strongly acidic) gives Sunflower a suitability score of 43/100. Apply agricultural lime before planting to unlock phosphorus and lift the score.

Nyandarua County is a challenging environment for Sunflower (soil-match score 43/100) and will need significant amendment before planting. At an average pH of 5.38 the soil is moderately acidic, below Sunflower's preferred 6–7.5 range; agricultural lime will lift pH and unlock phosphorus the crop cannot otherwise access. Nitrogen (1.28 g/kg), phosphorus (14 mg/kg) and potassium (166 mg/kg) all meet Sunflower's requirements, so a maintenance fertilizer programme is enough. Sunflower prefers sandy soils, while Nyandarua is largely clay, so drainage and organic-matter management matter more here. On ShambaIQ's soil-match model, Sunflower is the #77 soil match of the 106 crops we assess for Nyandarua County. Sunflower's full potential is about 750 kg/acre (~KES 36,000/acre at KES 48/kg), but at Nyandarua's 43/100 suitability a realistic target here is closer to 403 kg/acre (~KES 19,344/acre) unless the constraints above are addressed.

Better matched to Nyandarua's soil: Tea, Pyrethrum, and Potato — each scores higher on the same soil.

43Suitability score

Soil & climate match

FactorNyandarua soilSunflower needsStatus
pH5.3867.5Adjust
Nitrogen1.28 g/kgmin 0.8 g/kgOK
Phosphorus14 mg/kgmin 12 mg/kgOK
Potassium166 mg/kgmin 150 mg/kgOK
Rainfall1,100 mm400–800 mmHigh
Altitude2,300 m0–2,000 mHigh

Planting calendar for Nyandarua

Long Rains· MarchMayMain season here

March
Sowing & Basal Fertilizer
April
Top Dressing & Weed Control
May
Head Development & Bird Protection

Short Rains· OctoberDecember

October
Sowing & Basal Fertilizer
November
Top Dressing & 1st Weeding
December
Harvesting & Drying

Dry Season· JanuaryMarch

January
Harvesting & Threshing
February
Land Resting
March
Seed Selection & Storage

Top dressing guide

Product
CAN
Timing
Week 4–5 after emergence
Instruction
Apply at vegetative stage before flower bud initiation.
Bags per acre in Nyandarua
0.5

Nyandarua's nitrogen (1.28 g/kg) already meets Sunflower's 0.8 g/kg requirement, so this is a maintenance rate.

Recommended seed varieties

No variety in our list is specifically rated for Nyandarua's 2,300 m altitude and 1,100 mm rainfall, so all 2 are shown. Confirm with your agrovet before buying.

Kenya FedhaMedium/Dryland
Kenya Seed Company · 90-110 days · 8-12 bags/acre
High oil content (40-45%); resistant to downy mildew.
H8998Medium
Pannar Seeds · 85-100 days · 10-14 bags/acre
Hybrid; very high oil yield; uniform heads.

Economics

Market priceKES 48/kg
Expected yield in Nyandarua403 kg/acre
Estimated revenueKES 19,344/acre
Adjusted for Nyandarua's 43/100 suitability. Under ideal conditions Sunflower can reach 750 kg/acre (~KES 36,000/acre) — attainable here only after the climate and soil constraints below are addressed.

Preferred textureSandy

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