Quick stats
| Family | Fabaceae |
|---|---|
| Typical harvest | 2.1 t/ha |
| Varieties | 3 |
| Pests & diseases | 6 |
| Seasons | 3 |
Crop profile
| Growth habit | annual |
|---|---|
| Days to harvest | 110 |
| Main uses | Grain for whole beans, flour, soya milk and animal feed; also used for oil and cake. |
| Pollination | self |
| Origin / where it grows | Soybean is grown in medium to high rainfall and irrigated areas in East Africa, often in rotation with maize or cereals. |
Weather, soil & spacing
| Best temperature | 20–30 °C |
|---|---|
| Rainfall | 500–900 mm/yr |
| Altitude | 0–1800 m |
| Best pH | 6–7 |
| Soil type | Wide range; best in well-drained soils |
| Row spacing | 45 cm |
| Plant spacing | 5 cm |
| Planting depth | 3 cm |
| Seed rate | 60 kg/ha |
| Nursery days | — |
Simple notes for farmers
About the crop: This crop is annual. You plant, grow and harvest it in one main season, then plant again. You can normally start harvesting about 110 days after planting, depending on care and variety.
Main use: Farmers mostly grow this crop for grain for whole beans, flour, soya milk and animal feed; also used for oil and cake..
Pollination: This crop is mainly pollinated by self. Keeping flowers healthy and having insects like bees in the field helps improve fruit set and yields.
Where it grows: Soybean is grown in medium to high rainfall and irrigated areas in East Africa, often in rotation with maize or cereals. It is grouped under: Legumes & Pulses.
Best climate: This crop does well in warm areas where the temperature is usually between 20 and 30 degrees Celsius. It prefers places that receive around 500 to 900 millimetres of rain in a year. It can grow from near sea level up to about 1800 metres above sea level.
Soil: The crop grows best in slightly acidic to near neutral soils, with a pH of about 6 to 7. Choose a fertile, well-drained soil. Avoid places where water stands for long periods.
Plant spacing: Plant in rows about 45 centimetres apart, and leave about 5 centimetres between plants in the row. This gives each plant enough space for roots and canopy to spread.
Planting depth: Dig planting holes or furrows about 3 centimetres deep so the roots sit firmly in the soil but are not buried too deep.
Seed or planting material: Use around 60 kilograms of seed or planting material per hectare. Spread or plant evenly so the field has a good stand without being overcrowded.
Farmer guide (mwongozo wa mkulima)
Nutrient schedule (mbolea kwa hatua)
| # | Stage | DAP | Product | Rate | Targets (kg/ha) | Notes |
|---|---|---|---|---|---|---|
| 1 | Basal at planting | 0 | NPK with P (e.g., 0-23-19) or TSP + K source | 80 kg/ha | N: 0, P₂O₅: 30, K₂O: 20 | Band fertilizer 5 cm away from the seed row; inoculate Soybean seed before planting where needed. |
| 2 | Optional K topdress (early podding) | 40 | Muriate of potash (MOP) | 30 kg/ha | N: 0, P₂O₅: 0, K₂O: 18 | Use mainly where Soybean straw is removed and soils test low in potassium. |
Nutrient requirements
| Nutrient | Stage | Amount | Unit |
|---|---|---|---|
| N | Basal | 0 | kg/ha |
| P₂O₅ | Basal | 30 | kg/ha |
| K₂O | Basal | 20 | kg/ha |
| N | Topdress_early | 0 | kg/ha |
| P₂O₅ | Topdress_early | 0 | kg/ha |
| K₂O | Topdress_early | 20 | kg/ha |
| Name | Country | Maturity | Traits |
|---|---|---|---|
| Medium-maturing soybean variety | KE | 110 | Good grain yield, suited to medium rainfall zones and rotations with maize. |
| Early soybean variety | TZ | 95 | Early harvest, fits short seasons and double cropping. |
| Local soybean type | KE | 115 | Traditional taste and cooking quality, moderate yield. |
| Stage | Product | Rate (kg/ha) | Notes |
|---|---|---|---|
| Basal | NPK with P (e.g., 0-23-19) or TSP + K | 80 | Supplies phosphorus and potassium for Soybean root growth and nodulation. |
| Topdress (optional K) | Muriate of potash (MOP) | 30 | Use in K-deficient fields to support pod fill and standability. |
| Name | Type | Symptoms | Management |
|---|---|---|---|
| Soybean aphids | pest | Clusters of small insects on new leaves and stems; leaves curl and plants may look sticky or sooty. | Encourage natural enemies and use selective insecticides only when aphid numbers are very high. |
| Defoliating caterpillars | pest | Chewed leaves and leaf holes; in heavy attacks, plants of Soybean may be almost bare. | Scout regularly and spray with recommended products when damage exceeds acceptable levels. |
| Pod-sucking bugs | pest | Shriveled or flat seeds, brown feeding spots on pods. | Avoid very late planting, keep field edges clean and spray if many bugs are present during pod fill. |
| Rust | disease | Small brown to orange spots on leaves that later drop, leaving bare stems. | Use tolerant Soybean varieties and apply fungicides where rust pressure is high and economic. |
| Bacterial pustule and leaf spots | disease | Small raised spots or larger dead patches on leaves; premature leaf drop. | Use clean seed, rotate crops and avoid overhead irrigation late in the day. |
| Storage beetles and weevils | pest | Holes and powder in stored Soybean grain; live beetles in bags. | Dry well, cool grain before storage and use airtight or treated bags. |
| System | Typical | Min | Max | Notes |
|---|---|---|---|---|
| Smallholder rainfed (low input) | 1.2 | 0.7 | 1.8 | Local or mixed seed, little fertilizer, basic weed control. |
| Smallholder rainfed (improved management) | 2 | 1.5 | 2.5 | Improved varieties, inoculation, starter P, timely weeding and pest control. |
| High input / irrigated | 3 | 2.5 | 4 | Good varieties, inoculation, balanced nutrients and reliable water. |
| Country | Region | Planting | Harvest |
|---|---|---|---|
| KE | Medium to high rainfall Soybean areas (long rains) | Mar–Apr | Jul–Aug |
| KE | Medium rainfall areas (short rains) | Oct–Nov | Feb–Mar |
| TZ | Southern highlands and lake zones | Nov–Dec | Apr–May |
| Country | Region | Suitability |
|---|---|---|
| KE | Medium to high rainfall maize–Soybean belt | High |
| KE | Very dry lowlands | Low |
| TZ | Southern highlands and lake Soybean areas | High |
| UG | Medium rainfall mixed farming zones | High |