Some facts to note from KARI
- The mineral nutrient content and solubility of a fertilizer in water determines its efficiency.
- How it works is affected by rainfall and temperature. It should have adequate moisture. To go into solution, but “Too much moisture is not good for fertilizer because it enhances loss through leaching and erosion.
- Nutrient status, pH, clay content and organic matter content can also influence the efficiency of fertiliser. Different crop species accumulate nutrients differently, even under the same soil fertility levels. “Every crop has a specific recipe for nutrient requirements unique to itself,” says Kari.
- Fertilizer method application, stage of plant, time and frequency can also influence its performance.
- Fertilizers can be applied through broadcasting, side banding, placing with seed, top-dressing, foliar applications and applying organic fertilizer. With broadcasting, fertilizers are applied uniformly over the field before planting the crop. It is incorporated into through tillage or cultivation. Inside band, fertilizers are applied in bands to one or both sides of the seeder plant. Another method is where the fertiliser is put in the hole then covered with soil before the seed is placed. Topdressing is applied to the crop after emergence. Foliar fertilizer insoluble and applied directly to the top part of the plant.
- Incorporate organic fertilizer the soil because they require microbial activity to break down and also helps reduce gaseous lose of nutrients, especially nitrogen.
- Apply organic fertilizers regularly, preferably annually, to maintain and increase current levels of soil organic carbon and total nitrogen contents among other nutrients “How often and at what stage to apply fertilizers determined by the type of the crop and element, convenience and cost,” says Kari. Before planting have the soil tested regularly to determine the nutrients required and in what form.
- Grow crops in rotation to avoid nutrient imbalance and depletion caused by continual removal of some nutrients at the expense of others. Crop rotations are also beneficial in disease and pest control because they help to break the cycles of pests and diseases.
- Keep the fertilized crops weed free. Weeds compete for essential nutrients with crops and can reduce yields by 50 per cent.
Some common mistakes farmers make in fertilizer application:
- Applying the wrong fertilizer.
- Over liming
- Applying the wrong amount like many farmers does: Some use too little fertilizer or too much of the same type causing an imbalance.
- Placing fertilizer at the wrong place canals has an effect on plant growth. If a soluble fertilizer is placed on top of the ground it can volatilize or erode, and those nutrients are lost.
- Applying fertilizer or top dressing at the wrong time will mean losing maximum benefits