- Cropping every year without replenishing these nutrients leads to decline in soil fertility.
- The quick remedy is for farmers to switch to non-acidifying fertilisers to avoid making a bad situation worse.
- The focus is to ensure supply of key nutrients for each crop to drive increased crop productivity and quality at a relatively low cost to the farmers, ease of application and non-acidification of the soils.
- For poor economies like ours where food security is still elusive and subsistence farming the mainstay, we need to embrace modern technologies that can swiftly change the dire situation while being watchful of our environment.
WILLIAM NGENO is the country manager of Yara East Africa, a fertiliser-making company. He spoke to Anita Chepkoech on how farmers can boost their soil fertility to improve production
Studies have shown that soil fertility across Kenya is declining, with most soils becoming acidic due to overuse of fertiliser. What is the remedy to this?
There are two aspects relating to this situation. One, farmers have continually applied only two nutrients, that is nitrogen and phosphorous, through the common fertilisers such as DAP, urea and CAN.
Every cropping season, the plants extract available nutrients from the soil and need more than 10 key nutrients for proper growth.
Therefore, cropping every year without replenishing these nutrients leads to decline in soil fertility.
The solution here is to utilise enriched fertilisers that provide both macro and micronutrients to suit the crop demand and nutrient removal.
By doing this, one ensures that continuous cropping doesn’t lead to soil mining. Retention of crop residues on-farm will also contribute to increasing soil fertility, therefore farmers should desist from burning crop residues.
Second, more than 63 per cent of the country’s soils are acidic, which means most of the fertilisers being used like sulphate of ammonia and DAP contribute to soil acidity.
The quick remedy is for farmers to switch to non-acidifying fertilisers to avoid making a bad situation worse.
But the long-term sustainable solution is to incorporate liming programmes into the cropping plans and in 4-5 years, acidity will reduce.