Organic fertilizer solution to soil fertility and environmental protection

 … As Mwanamambo says the use of organic fertilizer can sustain and optimize crop production while minimizing the environmental impact.

By Francis Maingaila

Lusaka (7-08-22 - Zambia24) - A consortium of Civil Society Organizations (CSO) advocating not only for indignant seeds but also sovereignty food security and nutrition have outlined the need for farmers to use organic fertilizer as a measure to enhance soil fertility, sustain plant growth and optimize crop production while minimizing the environmental impact.

The CSOs severally, collectively, and individually told Zambia24 in separate interviews that advancing food security and environmental sustainability in farming systems requires an integrated soil fertility management approach that maximizes crop production while minimizing the mining of soil nutrient reserves and the degradation of the physical and chemical properties of soil that can lead to land degradation, including soil erosion.

For instance, ActionAid Zambia, is encouraging farmers to adopt a farming strategy called agroecology for healthy food systems and environmental protection.

ActionAid is also working with partners to find different approaches to efficiently manage soil fertility, thereby supporting the intensification of crop production and the preservation of natural resources.

ActionAid Manager for Resilient Livelihood and Climate Justice,  David Mwanamambo told Zambia24 in an exclusive interview that soil fertility management practices include the use of organic fertilizers inputs, crop rotation with legumes and the use of improved germplasm, combined with the knowledge on how to adapt these practices to local conditions will help to remove acid in the soil that impinges production.

ActionAid Manager for Resilient Livelihood and Climate Justice, 
David Mwanamambo

Mwanamambo said an integrated soil fertility management aims at maximizing the efficiency of the agronomic use of nutrients and improving crop productivity.

He said the use of grain legumes, which enhance soil fertility through the application of green manure, a key value of leguminous crops lies in the ability to fix atmospheric nitrogen, which helps reduce the use of commercial nitrogen fertilizer and enhances soil fertility.

According to Mwanamambo, nitrogen-fixing legumes are the basis for sustainable farming systems that incorporate integrated nutrient management.

He said soil fertility can further be improved by incorporating cover crops that add organic matter to the soil, leading to improved soil structure and promoting a healthy, fertile soil through green manure to replenish losses through plant uptake and other processes; and by minimizing losses through leaching below the crop rooting zone by improved water and nutrient application.

He explained that this system of farming helps improve and sustain the environment while you get your increasing production.

ActionAid Zambia is also calling on the government to support this farming approach by removing the subsidies on inorganic fertilizers and focusing on improving the manufacturing, sale, and distribution of organic fertilizers.

“We are calling on the government to move away from subsidizing synthetic fertilizers and put those funds into the production of organic fertilizer so that we will have more infrastructure for the production of compost for our farmers”, he said.

He added that “the synthetic fertilizers are not sustainable. It is very clear that over the past few years, farmers are struggling because they have not had synthetic fertilizers that come from outside.”

Mwanamambo disclosed that about 800 farmers have been trained in agroecological skills in zones that are affected by the effects of climate change.

He said particular interest will be in zone one including Southern and Western Provinces where draught has been prevalent in the recent past and Zone 3 including Northern Province which had too many rains.

ActionAid Zambia’s call for the use of organic fertilizers is in tandem with calls made by  Participatory Ecological Land Use Management (PELUM) Zambia that called on the government to consider subsidizing organic fertilizers for small and medium-scale farmers.

PELUM programs Manager, Wilfred Miga told  Zambia24 in an exclusive interview that rather than the usual subsidies on inorganic fertilizers which affect the composition of the soil, in the long run, the government should consider incentivizing farmers to forgo inorganic fertilizers for organic ones.

Miga said a find it unfortunate that successive governments continue to dawdle in the politics of ‘which government has brought in the most inorganic fertilizers”.

He said even more worrying is the fact that farmer associations in the country, who should know better, also dabble in the politics of fertilizers.

Miga advised farmers not only to completely move away from the use of conventional fertilizers but also to embrace organic fertilizer for better health food production and environmental protection.

PELUM is against the use of conventional fertilizer on account that
it increases soil acidity

He said PELUM is against the use of conventional fertilizer on account that it increases soil acidity in most of Zambia’s arable land and has greatly contributed to dwindling yields in recent times.

Miga said the continued use of chemicals to promote high yields and control pests have massively reduced production in most arable soils across the country.

A recently produced FAO Southern African report revealed that continuous use of fertilizers has resulted in reduced soil pH and declining productivity.

The report approximated those 7.5 million hectares of arable land in Zambia especially where crop production has reduced are highly acidic.

The normal PH levels in the soil suitable for crop production is 6.5-7 but according to the report, most of the arable land recorded levels below 5.5.

As part of a rescue plan for the soils, Miga recommended that farmers shift from the traditional fertilizers and embrace organic fertilizers that can fix acidic soils because it does not contain phosphoric acid which is now responsible for soil intoxication.

Miga explained that there can never be meaningful crop yield on a farm whose soil is highly intoxicated with acid coming from chemicals applied on farms to support production.

According to Miga, the phosphoric acid that is accumulated in the soil over time due to continued use of fertilizer blocks the root system of the plant and therefore prevents it from absorbing the nutrients.

"This is the reason why farmers in many parts of the country continue to complain of poor crop growth with maize characterized with stunted growth and yellowing of leaves,” he added.

To fix soil fertility as well as tripling yields Miga proposed that farmers be advised to use high calcium agricultural lime and those who cannot afford it can use ashes as an alternative solution.