Growing Rosemary in Kiambu

Soil suitability analysis based on Kiambu's nutrient profile

Quick answer

Yes, with the right inputs — Kiambu is moderately suited to Rosemary. Kiambu's soil (pH 5.28, strongly acidic) gives Rosemary a suitability score of 56/100. Apply agricultural lime before planting to unlock phosphorus and lift the score.

Rosemary can be grown in Kiambu County, but the soil scores 56/100 and needs targeted management to reach full potential. At an average pH of 5.28 the soil is moderately acidic, below Rosemary's preferred 6–8 range; agricultural lime will lift pH and unlock phosphorus the crop cannot otherwise access. Nitrogen (1.01 g/kg), phosphorus (13.7 mg/kg) and potassium (169 mg/kg) all meet Rosemary's requirements, so a maintenance fertilizer programme is enough. Rosemary prefers sandy loam soils, while Kiambu is largely clay, so drainage and organic-matter management matter more here. On ShambaIQ's soil-match model, Rosemary is the #77 soil match of the 106 crops we assess for Kiambu County. Rosemary's full potential is about 2,500 kg/acre (~KES 375,000/acre at KES 150/kg), but at Kiambu's 56/100 suitability a realistic target here is closer to 1,750 kg/acre (~KES 262,500/acre) unless the constraints above are addressed.

Better matched to Kiambu's soil: Macadamia, Avocado, and Pineapple — each scores higher on the same soil.

56Suitability score

Soil & climate match

FactorKiambu soilRosemary needsStatus
pH5.2868Adjust
Nitrogen1.01 g/kgmin 0.8 g/kgOK
Phosphorus13.7 mg/kgmin 12 mg/kgOK
Potassium169 mg/kgmin 150 mg/kgOK
Rainfall1,100 mm400–900 mmHigh
Altitude1,700 m800–2,400 mOK

Planting calendar for Kiambu

Long Rains· MarchMayMain season here

March
Cutting Establishment
April
Weeding & Light Feeding
May
Harvest & Pruning

Short Rains· OctoberDecember

October
Cutting Establishment
November
Weeding
December
Harvest & Pruning

Top dressing guide

Product
CAN
Timing
Twice per season
Instruction
Light feeder — over-feeding reduces oil content and hardiness.
Bags per acre in Kiambu
0.250.2

Kiambu's nitrogen (1.01 g/kg) already meets Rosemary's 0.8 g/kg requirement, so this is a maintenance rate.

Economics

Market priceKES 150/kg
Expected yield in Kiambu1,750 kg/acre
Estimated revenueKES 262,500/acre
Adjusted for Kiambu's 56/100 suitability. Under ideal conditions Rosemary can reach 2,500 kg/acre (~KES 375,000/acre) — attainable here only after the climate and soil constraints below are addressed.

Preferred textureSandy Loam

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