Whoever chooses to invest in farming is interested in having a bumper harvest, which calls for the application of fertilisers. The two types of fertilisers are organic and inorganic.
Organic fertilisers, according to the African Fertiliser Agribusiness Partnership (AFAP), are made from natural or living materials such as peat moss, bone, seaweed, composted plant materials, and animal manure.
On the other hand, synthetic or inorganic fertilisers are manufactured chemically or produced from rocks and minerals.
Organic fertilisers include foliar and compost manure, while inorganic include manufactured fertilisers such as NPK and DAP.
Noteworthy is that while inorganic fertilisers contain all the nutrients needed by the soil, the case is different with organic fertilisers as most of them have little or no nitrogen, according to soil scientists.
When to apply fertiliser
Prof. Zaake of Bio Fertiliser Africa said soil testing, during which experts take samples of soil across the plot in order to find the missing nutrients, is important.
When farmers know the missing nutrients which are important for plant growth, they can invest in the exact nutrients.
Zaake says since most soils have lost fertility due to practices such as nutrient mining and loss of organic matter during harvest, soil erosion and leaching, soil testing is key.
Soil testing services are currently being offered at National Agricultural Research Organisation (NARO) laboratories in Kawanda, Makerere University and private companies such as Hollands Soil Care, which uses scanners to test soils.
Dr Kayuki Kaizzi, a senior soil scientist at NARO, advises farmers to look out for quality fertilisers, especially from registered agro-dealers and fertiliser manufacturing companies.
He adds that whether one chooses to use organic or inorganic, all these revive the soil to promote plant growth and better yields.
Richard Mugisha, a research assistant to Prof. Zaake, explained that organic fertiliser maintains all organisms in the soil, maintains natural processes of soil regeneration and that it can be used without destroying the biodiversity.
The other advantage is that organic fertiliser is not poisonous to soil organisms, instead its food to the soil organisms.
Soil scientists add that organic fertilisers improve the soil texture, allow the soil to draw as much water and nutrients to plant as possible and also promote the growth of useful bacteria and worms that help in creating air and water spaces in the soil.
Uganda’s soil status
According to soil scientists from the National Agriculture Research Laboratories (Kawanda), Ugandan soils across the country have lost fertility due to over-cultivation, soil erosion and failure to apply fertilisers, among others.
The scientists add that by farmers ignoring traditional soil conservation practices such as terracing, most of the top soil has been lost through surface run-off and floods that sweep away the top soil full of nutrients.
The experts said the fertility lost includes 21kg of nitrogen, 8kg of phosphorus and 43kg of potassium per hectare per year.
They also said the current fertiliser usage has stagnated at less than 1kg per hectare per year.
While applying the fertiliser, eating or drinking is not allowed as one can easily inhale the chemicals that can be harmful to their health.
NuGro Bio activator, a foliar plant growth exhibitor, has anti-fungal and anti-bacterium properties. This also increases the uptake of NPK from the soil, and promotes seed germination. For better yields, it’s first mixed with seed before planting.