Moses Tamale, a farmer in Buwambo, Wakiso district, has planted maize for the second time on his two-acre piece of land. In the first season, the harvest was not as much as he expected, but he says it was okay, since it was the first time.
“There are things that I did not do well, for example adding the right amounts of fertilisers to the soils,” he says.
According to Prof. Kitungulu Zaake, a soil scientist, soils in Uganda have been over used and need to be replenished with relevant fertilisers.
The challenge for farmers, however, is that they do not know how much fertilisers to use.
“Most farmers do not apply fertilisers at all and those who apply do it through guess work,” he says.
To know the right amounts of nutrients required by the soils, you must handle and treat the soil well. Uganda has got many soil types, including those that are acidic, alkaline and each type has to be treated differently, if a farmer is to get good yields.
Gerald Mayanja, an agriculturalist and a soil technician, attributes the poor farmers’ harvest to lack of information on their soils and the ideal crops they support.
He says most of the farmers in the country do not know the type of soil that is suitable for their crops. The acidity in the soil is what determines whether the soil type is good for the crop or not.
Mayanja says if the crop is planted in a type of soil that is not suitable for it, the yield will be poor. How to know that the soil is suitable for your crops After deciding on the crop you want to grow, you need to take a sample of your soil for testing. The nutrient deficiency of the soil is not seen by just looking at it or feeling it in your palms. Begin by taking a sample of the area you want to use for farming to a laboratory for testing.
There are soil testing facilities at regional agriculture research centres in each region in the country.
But to get the right test, you must handle the process of selecting the soil test samples carefully.
“Do not use your bare hands to carry the samples as you might mix in sweat and distort the results,” Mayanja advises.
He notes that when taking the samples from an area, observe the crops growing there. Observe out the colour of the leaves and make sure you describe it to the experts.
Why should one test their soil?
“Soil is the beginning and end of life,” Mayanja says. It is very important to know the nature of the soil before planting any crop. The alkalinity and acidity of soil is measured on a scale known as pH.
Mayanja says the soil with high levels of acidity supports crops such as tea while sugarcane requires low levels of acidity.
He further says testing the soil will help you know the kind of microorganisms it.
“Treat soil the way you want to be treated, with love, since it is the most important asset for farmers,” Mayanja says.
He says once you know the kind of soil you have, you plant the right crop. When spraying, Mayanja urges farmers to use material appropriate for the size of the crop.
A lot of digging during weeding is also not good for the soil.
Mayanja advises farmers to avoid too much digging by planting ground covering plants like beans, to control weed growth.
Key requirements for crops to perform
When a previously forested area is used for growing crops for the first time, the soil usually contains all the nutrients that the plants need.
However, with time, the amount of nutrients decrease to levels which are not enough to support growth and development. Without giving back organic matter to the soil (as the forest did before) the yield is expected to decrease. T
he nutrients in the soil, however, are not always fixed. Hence, even if the total amount of nutrients in the soil is high, deficiency symptoms still occur. Plants require 16 nutrient elements, 13 of which come directly from the soil (mineral elements).
Not all are required for all plants, but all have been found essential to some, hence are termed as essential elements.