DRC: Farmers use local herb to fight weeds, restore land, increase production

December 02, 2018
A translation for this article is available in French

Sylvestre Muhindo thrusts his right hand into the soil in the middle of his field and pulls out a handful of wet earth. His face isn’t usually so relaxed after the harvest. He gazes over his land and sees that weeds like quack grass, called chiendent in the local language, have disappeared, and that his field is covered with decomposing mukuna foliage.

Mr. Muhindo is a 40-year-old farmer who lives in Kibututu, a village in the province of North Kivu in the Democratic Republic of Congo. He grows cassava on a half-hectare field.

For many years, Mr. Muhindo’s soil was becoming more and more compacted, and weeds took over nearly all his land right after the harvest. According to Mr. Muhindo, the land became harder and less fertile because of prolonged drought. As a result, the cassava plants were no longer growing as well.

He recalls, “I was distressed by the disturbance of the growing season, with the long absence of rain.”

Before, he used to sell five or six bags of cassava a year, each weighing 110 to 120 kilograms, for an average income of $150 US. But his production fell by half.

This made it difficult for him to pay for labour, seeds, weeding, and monitoring.

Mr. Muhindo adds, “One of my three sons had to drop out of school for lack of money and help me monitor the field for thefts.” He was about to stop growing cassava when he discovered mukuna.

In February 2016, he met a group of farmers who convinced him to try mukuna before making a final decision about his cassava. Mukuna is the Swahili name for Mucuna pruriens, a climbing plant in the pulse family that is also known as velvet bean. Some farmers plant mukuna after harvest and leave it to grow for several seasons. Mukuna establishes a thick ground cover that suppresses weeds. And, because it’s a legume, it feeds the soil with nitrogen.

Mr. Muhindo visited an NGO called Centre de Développement Rural de Kibututu, or CEDERU. The organization gave him three kilograms of mukuna seeds for free, which he planted. After 15 days, the plant had begun to take over the field, climbing on the cassava stalks that remained. The mukuna quickly covered the soil, making sure that weeds couldn’t reach the sunlight.

Mr. Muhindo says: “My field was, for a long time, covered by uncontrollable weeds. All of a sudden, there were none and I was very happy. When I saw that the soil had also become moist unlike it had been before, I burst with joy.”

Mr. Muhindo’s production has doubled. Last year, he harvested a dozen bags of cassava, which he sold for $30 US per bag in the local market.

Adela Chizamenya is a 45-year-old farmer who grows maize in Kiseguro, a small village not far from Kibututu in the chiefdom of Bwisha. This “miracle plant” has helped farmers like her to decrease her workload and the cost of production.

She purchased mukuna seeds for 2,500 CFA (about $5 US) per kilogram. She planted two seeds per hole. Each hole is 40 centimetres apart and each row is also 40 centimetres apart. One month later, she found that the cover crop had effectively excluded the weeds.

Mrs. Chizamenya explains: “The soil became very soft so that I didn’t need to labour in my field any more … I just broke the soil and planted the maize. I did not return until three months later for harvest. I didn’t work like before. And I harvested even more.”

Mrs. Chizamenya harvested 13 bags of maize, compared to the seven that she had previously harvested. Each bag weighs about 115 kilograms and sells for about $25 US.

Mukuna improves the texture and fertility of the soil, as well as suppressing weeds. Mukuna fertilizes the soil by adding nitrogen, “a primary fertilizer,” according to Oscar Hangi, agronomist at CEDERU.

Mr. Hangi says: “Mukuna kills the weeds and prevents erosion by gradually becoming more and more common in the field. The green matter that its produces in abundance in the field decomposes easily to create humus, a mineral element that fertilizes and colours the soil.”

Mukuna also produces lots of vegetation. As this decomposes, it helps water filter slowly into the soil, where it is retained.

CEDERU has been leading extension campaigns to teach farmers in North Kivu about this plant. Using mukuna can help farmers adapt to the variable climate that is affecting fields.