Even seemingly simple tasks, like raising the humble earthworm, can be done in more ways than one, however all variations must follow certain basic principles.

In a video from Bangladesh, villagers show the audience how to raise earthworms in cement rings, sunk into the soil. The floor is covered with a sheet of plastic to keep the worms from escaping. The worms are fed on chunks of banana corm and the ring is covered to keep out the rain, but still retain some moisture.