Happy Mafie’s farm is green and looks well-managed. Her Canavalia beans cover the soil so well that the hot sun doesn’t dry it out, and the rains don’t wash it away. She is practicing conservation agriculture, with Canavalia beans acting as a cover crop on most of her farm.
Mrs. Mafie is from Njeku village in northern Tanzania’s Arumeru District. She and her husband grow mostly coffee and banana on a slope at the foot of Mount Meru. They also grow spinach, hot peppers, vanilla, papaya, and passion fruit. Between harvests, she plants Canavalia beans. She also intercrops the beans with maize.
She explains, “We started with 10 kilograms of Canavalia beans, but now we have 100 [60-kg] bags. [The beans] have helped us to harvest more maize and bananas.”
Mrs. Mafie says Canavalia beans are a cover crop that helps improve soil fertility by increasing nitrogen levels in the soil. It also shades the soil, conserving moisture and reducing erosion. According to Mrs. Mafie, this means she always has a good maize harvest, even during dry spells.
She learned how to grow Canavalia beans from the East Africa Impact Center. When extension officer Charles Boniventure visited Mrs. Mafie’s compound, he suggested she use green manure or cover crops to protect her soil. He says, “Growing Canavalia beans in between any plants helps, as it acts like a fertilizer that helps the plant to grow more quickly.”
Mr. Boniventure adds, “We have tried to increase the use of Canavalia, which has helped us a great deal because after planting there was an increase in the yield compared with previous years.”
The extension officer gave Mrs. Mafie one sack of Canavalia seeds, which she planted after harvesting her maize.
Now she makes good money selling Canavalia beans to other farmers, who use them for seeds or for food. She adds, “We sell one kilogram of Canavalia at 15,000 Tanzania shillings [US$6.50].”
Other farmers and extension workers visit Mrs. Mafie’s farm to learn how she uses Canavalia beans in conservation farming.
She hopes that many farmers in her area will start using Canavalia beans as a cover crop. She says her family will continue looking for ways to use Canavalia to further support their farm.
This work was created with the support of Canadian Foodgrains Bank as part of the project, “Conservation Agriculture for building resilience, a climate smart agriculture approach.” This work is funded by the Government of Canada, through Global Affairs Canada, www.international.gc.ca .
Photo credit: Dinesh Valke