Groundnut has been reported to respond better to residual fertility than to direct fertilization. its energy requirements need to be met with the application of optimum quantities of plant nutrients through application of manures and fertilizers.
Groundnut requires adequate levels of phosphorus, potassium, magnesium and particularly calcium, which are required for maximizing yield and good quality seed.
For farmers who can afford artificial fertilizers, application of Single Super Phosphate, (SSP) at the rate of 100-125 kg/ha or Triple Super Phosphate (TSP) at 80-90 kg/ha will boost yield.
Groundnut farmers must note that liming is necessary only when the soil pH is below 5.8. However, if soil test results are not available, the general fertilizer recommendation of NPK kg ha-1 is 25 kg of N – 50 kg of P2O5 – 100 kg of K2O.
DISEASE AND PEST CONTROL
Use rosette resistant varieties of groundnut e.g. Serenut 2, Igola 1 etc to eliminate the need for spraying insecticides to control the aphids. Avoid late planting and wide spacing to reduce incidences of rosette disease.
If a high yielding non-rosette resistant variety is grown (e.g. Serenut 1) then insecticides will be needed. Systematic insecticides such as dimethoate (Rogor EC40) can be sprayed at 10-day intervals for a total of four sprays.
Since the leaf spot pathogens survive mainly in crop debris, cultural practices such as crop rotation, burying crop debris during land preparation and early sowing can significantly reduce the incidence of the diseases. Avoid growing groundnut in fields that have history of termites.
WEEDING & MANURE
Weeding and adding manure to groundnut is the same as in potato. But, you have to weed the guinea corn twice since it takes about 5 -6 months for it to mature.
Groundnuts mature from 90-130 days depending on the variety. Early or premature harvesting, lowers the yield, oil quantity, and seed quality.
Plants from immaturely harvested seeds 13 germinate slowly and have low vigor and their survival can be difficult under stressful conditions. Mature nuts should be firm and dry and brown on the outside. The inside of the pods should be grey and produce a rattling sound when shaken.
Groundnut can be harvested either by hand pulling the entire plant (this is possible only when there is enough moisture in the soil) or using a hoe or ox-drawn plow (usually used for spreading groundnut varieties on heavy soils and during dry conditions). This method is effective in lifting the entire crop from soils, with low pod loss.
It is best to store groundnuts in their shell. Good drying of the pods to 7-8% moisture content will help to ensure that the seeds remain in good condition during storage. Never bag groundnuts for storage when the pods are still dump.
Before storing, poor, damaged shriveled, rotten, or fungus-infected pods should be removed. Whatever the storage container, it is important to ensure that the store is dry and that there is good ventilation so that the pods/seeds do not increase in moisture content, which would encourage fungal growth.