- Rainfall of 1,016mm is sufficient for the growth of groundnuts. They require five months of warm weather, and an annual rainfall of 500 to 1000mm or the equivalent in irrigation water.
- The water requirement is greater at flowering, pegging and pod filling.
- Dry weather is required for harvesting and drying.
- The plant cannot tolerate water logging.
- Well drained soils, preferably sandy loams with high Sulphur content and well aerated are required.
- Excessively heavy soils are not suitable.
Seeds are most commonly used. Larger seeds give better emergence and better yields. Maturity depends on the type used, but varies from 90 – 135 days (3 – 4.5 months).
- The seedbed should be fine and free of weeds.
- Sowing should be done in wet spells, in the first or second rains, to ensure rapid and even germination.
- Early planting is recommended to reduce the risk of rosette infection which increases as the season advances.
- Row planting at a spacing of 45cm x 15cm for spreading types such as Igola-1; 45cm x10cm for bunch types such as Red Beauty.
- Seeds should be planted 5 – 8 cm deep.
- The seed rate is 20 – 25 kg/acre for spreading types and 25 – 30 kg/acre for bunch types.
- Farmyard manure applied to the field before planting improves yield.
- Application of 10 – 12 ton per hectare of chicken manure or 20 ton per hectare of well-decomposed farmyard manure should be completed at least one month before sowing.
- This should be mixed into the soil for good plant development and to improve soil structure.
- Also, the use of a fertilizer combination of calcium, potassium and magnesium applied as Single Super Phosphate at the rate of 125kg/ha before planting will improve yield because the fertilizers promote nodulation.
- Weeds cause much damage to the groundnut crop during the first 45 days of its growth.
- Early weed control is critically important from 3 – 6 weeks after sowing in order to achieve maximum yields.
- Weeding two or three times is necessary in hand hoed fields.
- Herbicides, if applied judiciously, may be used, for example, round up.
- However, a combination of methods could be more effective and economical.
- Premature harvesting of groundnut pod slows the yield, oil percentage and quality of seeds.
- Harvest when the plants have shed their leaves and when the inside of the pod turns dark brown.
- Leave the groundnuts in windrows for 3 days before plucking.
- Harvested plants should be stacked in the field for a few days for air and sun drying before stripping the pods.
- Clean the pods by removing the soil and other dirt and dry properly before storing in a well ventilated place.
- Delay in harvesting after physiological maturity can result in increased Aspergillus flavus infection, and aflatoxin contamination in pods/seeds, and many pods may be left in the soil due to weakening of pegs.
Yield of local varieties range between 600 – 1000kg/ha with a national average of 800 kg/ha. With good husbandry, improved varieties can yield up to 3,500 kg/ha for example Igola-1 yields 3000 -3500 kg/ha, Red Beauty 1,900 – 2,500 kg/ha, Roxo 2,000 – 2,700 kg/ha, Igola-2 2,500 kg/ha and Serere Red 2,500 – 3,500 kg/ha.
- A crop rotation of groundnut-cereal-cereal helps in efficient nutrient utilization and reduces soil-borne diseases and nematodes.
- It also helps to reduce the incidence of weeds.
- Maize, sorghum, pearl millet, or small grain crops can be grown following groundnuts.
- To reduce the incidence of soil-borne diseases, it is recommended not to grow groundnut after tobacco or cotton.