Zambia: Fertilizer made from groundnut shells and leaves improves maize harvest

August 29, 2016
A translation for this article is available in French

Chosiwe Shanzi is innovating. She makes her own fertilizer to improve her maize harvest. Mrs. Shanzi has to be creative because soils are infertile where she lives in eastern Zambia’s Chipata district. And chemical fertilizer is getting more expensive.

Mrs. Shanzi and other farmers in Chipata district learned how to make alternative fertilizer from their conservation farming club. She explains: “Mr. Charlton Phiri, who has now retired from the Ministry of Agriculture, used to come to our club. One day he taught us about a simple technology that did not require costly inputs like chemical fertilizer, pesticides, and herbicides. This is called manure tea.”

Manure tea is a simple and effective source of nitrogen for fields, gardens, and orchards. Mr. Phiri explains that the technique involves putting grass and dry leaves from selected trees or shrubs into a sack, along with nitrogen-rich crop residues like groundnut stalks and soybean trash. The sack is suspended in a 200-litre drum of water and left until the contents rot. From time to time, the sack is shaken to release nutrients into the water. When the water changes colour and starts to smell terrible, the sack is removed.

Mr. Phiri explains, “Farmers can then use the water solution as liquid fertilizer to spray on their crops.”

Using leaves from leguminous trees and shrubs such as Gliricidia sepium, Sesbania sesban, and pigeon pea, along with crop residues from nitrogen-rich groundnut and soybean plants, ensures that the water solution is rich in nitrogen.

Mrs. Shanzi cares for four orphaned nieces and nephews, and could not afford a drum and sprayer to make manure tea. But she understood the importance of enriching her soil. So she collected groundnut shells from a nearby peanut factory and spread them throughout her maize field just before the rains began. To her surprise and happiness, this helped to enrich the soil. Many of her maize plants produced three large cobs, and her maize harvest tripled.

Her neighbour is shocked—and interested. Evelyn Zulu says, “This is unbelievable…. I will have to try it in my own field to believe [that] the three cobs that you got are the result of manure from groundnut shells.”

Grevasio Banda is another member of the conservation club. He says manure tea is effective for many things. He explains, “Besides being a fertilizer, manure tea also works like an insecticide against aphids and red spider mites if you spray it on leafy vegetables and tomatoes.”

Although Mrs. Shanzi doesn’t yet have a sprayer or drum, she is happy that using groundnut shells has been successful. She says: “This year I harvested enough maize by just using groundnut shells. I will sell the surplus and invest in a sprayer or drum with my profits. Then I shall be able to follow what Charlton taught us about how to make and use manure tea.”

Photo:  Chosiwe Shanzi  in her maize garden. Credit: Filius Jere