* Any views expressed in this article are those of the author and not of Thomson Reuters Foundation.Improved soils lead to better yields and higher incomes, reducing hunger
When Elizabeth Msimanga, a farmer in Zimbabwe’s Nkayi District, walks on her farmland, her feet make the sound “vuchu vuchu” as they sink into the soil. But on one plot of 82 by 75 metres, where she practices conservation agriculture, she says she has no problems.
“I can see the difference in soil structure and fertility,” Msimanga says. “My farm is on sandy soil, but on the field where I have been using conservation agriculture, the soil structure has really improved.”
Evidence suggests that poor soil fertility and degradation severely limit food security for many smallholder farmers in southern Africa. Productivity on rain-fed farms is low due to infertile soils, unreliable rainfall patterns often associated with prolonged dry spells, sparse infrastructure and restricted access to markets.
This is what Zimbabwean farmers like Msimanga struggle with - a situation made even worse by poor governance and an unfavourable macro-economic environment.
Like most of semi-arid southern Africa, Zimbabwe is predominantly dependent on rain-fed agricultural production, with more than half of the population currently food and nutrition-insecure.
But there are alternatives. Msimanga says practising conservation agriculture on part of her land has increased her yields and income. She heard of these soil and water conservation techniques in 2007 from the local AGRITEX (national extension agency) office, which provides farmers with extension support in Duha village.
“In the past I used to harvest about 450 kg of maize from my whole farm but now I get around 2,250-3,150 kg of grain. The conservation agriculture field contributes to most of this yield,” she says. “Before, I would only have one meal and water (a day). But now I have three meals.”
Conservation agriculture is based on three main principles. First, minimum soil disturbance, which means not tilling the land; second, leaving the remainder of the crop after harvest as a form of mulch to help soil retain moisture; and third, rotating cereals such as maize with other crops such as legumes, mainly cowpeas and groundnuts, which naturally regenerate soil nutrients.
The semi-arid region where Nkayi district is located is characterised by semi-subsistence farming, with yields averaging less than 600 kg per hectare for the main cereal, maize. Msimanga’s yield increase is exceptionally good, but farmers using conservation agriculture methods have often achieved yields that are 15 to 75 percent higher than with conventional practices.
Since 2004, the International Crops Research Institute for the Semi Arid Tropics (ICRISAT), with funding from the UK’s Department for International Development (DFID), has been promoting conservation techniques with partners like AGRITEX and NGOs including CARE, CAFOD, CRS, World Vision, Oxfam GB, Save the Children UK, Action Contre la Faim, Christian AID and Concern Worldwide.
One constraint is the need for labour. For example, conservation agriculture techniques include planting basins that conserve rainwater as well as enabling the precision application of nutrients. Manually digging these basins, instead of using oxen to plough a field, is much more labour-intensive.
But Msimanga and her family feel the benefits are worth it. From August to September, the months before the rains start, they prepare their plot. “We dig the basins when the soil is dry. If five people work together, we can prepare our field in a month,” she says.
“Weeding is a challenge, but we need to make sure we weed the plot well, as there is a big difference in yield if you don’t,” says Msimanga's granddaughter Promise. Research suggests that weeds gradually reduce, provided that diligent weeding takes place during the initial years. Once weed seeds are removed from the surface layer of the soil, those buried in the undisturbed soil remain dormant.
Besides increasing food security for Msimanga and her family of eight, conservation agriculture has also helped them raise their standard of living. With the money from selling the excess maize she produces, Msimanga has bought a cow and goats, built a new hut she uses as a kitchen, and is able to afford school fees for her grandchildren who live with her.
“I am old now,” she says smiling. “I am not looking to build wealth, but just want to make sure I have enough for myself and my family.”
The impact doesn’t stop there, however. Msimanga’s success with conservation techniques has encouraged a growing number of her neighbours to follow suit, resulting in improved community food security.
This article was written by ICRISAT researchers Kizito Mazvimavi and Martin Moyo, and communications officer Swathi Sridharan.