Digging manure pits to grow more vegetables

Mali: Digging manure pits to grow more vegetables

It is early morning in Walirde, a small village in Sévare, a neighbourhood in the northern Mali city of Mopti.

Fatoumata Diallo and some other women are already anxiously awaiting a specialist in making composted manure—Brehima Djiguiba. The 20 women are active market gardeners. Mrs. Diallo is president of their group, Yiriwere, which means “blossoming.”

In total, the women own two hectares of land. They each manage their own garden, where they grow many vegetables, including lettuce, cabbage, tomatoes, okra, and spinach. There is a ready market for their vegetables in neighbouring towns like Mopti.

But the women weren’t satisfied with their yields. So they decided to make composted manure to increase their harvest and save money. They got the idea from the radio program Nôkôdinguè ko (The question of manure holes), which airs on the Mopti regional station of the national broadcaster, ORTM (Office de Radiodiffusion Télévision du Mali).

The women asked Mr. Djiguiba to help them dig their first manure pit. Greeting Mr. Djiguiba, Mrs. Diallo says, “We are very happy that you have responded to our call because what we are doing together is very important for us and our market garden.”

Mr. Djiguiba starts by looking at the hole the women have prepared to make manure. It is one metre deep, two metres wide, and three-and-a-half metres long. The elements needed to make composted manure are nearby, including clay, which will stop moisture in the pit from seeping away into the ground, and potassium-rich ash, collected from the remnants of kitchen fires. The pit will also contain animal manure, grass, and dead animals such as birds.

To start the process, Mr. Djiguiba spreads clay over the whole pit, creating a layer five centimetres thick, half of which he waters. Then the women pound down the clay with their feet.

Next, the women spread grass about 20 centimetres deep, followed by animal manure and finally ash. They stamp down the pile and water it abundantly. The final layer completely fills the pit.

The women repeat the process at another pit, and mark the pits with two sticks. They will water the pits every 15 days. Composted manure requires a lot of water, which promotes decomposition.

After three months, they will remove the precious product from the pit, and each woman will receive some to use in her garden. Having composted manure means they won’t need to purchase synthetic fertilizer.

Referring to traders who sell synthetic fertilizers, Mrs. Diallo says, “We will become self-sufficient…. We will take the traders’ hands out of our pockets.” Imported synthetic fertilizer is expensive, and women in particular have a difficult time affording it.

Mr. Djiguiba explains two methods for making manure. One technique is to bury the ingredients underground or in a pit, as the women of Yiriwere have done. Alternatively, the ingredients can be placed in a box built for composting manure. The box must be at least one metre deep, but the length and width can vary.
Mr. Djiguiba says that it’s better to dig the pit in the shade. Sunlight diminishes the nutritional value and fertility of the compost.

After just three months, the women of Yiriwere will receive 600 kilograms of composted manure from their pit. From a two- by three metre-pit that’s one metre deep, they can produce enough compost to grow two hectares of any crop.

When they grow their crops, they will place the composted manure at the base of each plant. This increases the fertility of the soil and can boost their harvest. They hope the composted manure will result in a greater yield, but at least it will save them money.