Njahi, also known as Dolichos lablab, is a drought-tolerant legume widely grown in various parts of Kenya, particularly the Central, Western, and Eastern regions. It is celebrated for its nutritional richness, offering high levels of potassium, proteins, iron, phosphorus, folate, and magnesium. Both its beans and leaves are edible and can also be used as animal feed, making it a versatile crop that supports food security and income generation for small-scale farmers.
Common Varieties of Njahi in Kenya
- KAT DL 1
- KAT DL 2
- KAT DL 3
- Rongai
- DL 1002
- DL 1009
These varieties have been developed and selected for their adaptability, yield potential, and resilience against local pests and diseases.
Ecological Conditions for Njahi Farming
Njahi thrives under specific environmental conditions that support optimal growth and productivity:
- Soil: Prefers well-drained sandy-loam soils with a pH of 5.5 to 6.5.
- Altitude: Grows well at altitudes of about 500 to 1,800 meters above sea level.
- Temperature: Ideal temperatures range between 18°C and 28°C.
- Rainfall: Requires moderate rainfall of about 400 to 750 mm.
Planting Njahi in Kenya
Njahi can be directly sown in the field or started in a nursery before transplanting, though most Kenyan farmers prefer direct field planting. Planting should ideally coincide with the onset of the rainy season.
- Soil Preparation and Fertilizer:
Apply well-decomposed organic manure at planting. Additionally, about 30 kg of DAP fertilizer per acre can be used to enhance soil fertility. - Planting Spacing:
Maintain a spacing of approximately 30 cm between plants and 45 cm between rows to ensure adequate aeration and access to nutrients. - Weeding:
Regular weeding is essential to minimize competition for water and nutrients and to encourage healthy crop development.
Pests and Diseases Management
Common diseases that affect Njahi include stem rot, anthracnose, powdery mildew, and bacterial leaf spot. Nematodes such as M. incognita and M. hapla can also pose challenges.
Control Measures:
- Use appropriate, systemic insecticides as recommended by agricultural extension officers.
- Practice proper field hygiene, including crop rotation and timely removal of infected plants, to reduce disease spread.
Harvesting Njahi
Njahi generally matures and is ready for harvesting within 3 to 5 months after planting. Harvesting should be carried out once the pods have dried to ensure maximum quality and storability of the beans.
Market and Pricing
Njahi enjoys favorable market prices, both locally and internationally, due to its high nutritional value and relatively low production volumes. While prices may vary, a 90 kg bag of Njahi typically sells for between Kshs 5,000 and 7,000 in most local markets and cereal stores. Its superior nutritional profile and limited supply often result in better profits compared to other common legumes.
In conclusion, Njahi farming offers promising opportunities for Kenyan farmers looking to diversify their crops, improve their incomes, and contribute to food and nutritional security. With proper agronomic practices, disease management, and access to reliable markets, Njahi farming can serve as a sustainable venture for many small-scale growers in Kenya.

