Dar es Salaam, July 3 -- FOR years, farming in Ekenywa Village meant a familiar routine: buying chemical pesticides, hoping the rains would cooperate, praying pests would stay away and, at the end of the season, wondering whether the harvest would be enough to pay the bills. Today, however, farmers joke that some of the most powerful “farm workers” on their land are no longer found in bottles from agro-dealers for they grow on trees.

Neem, once just another shade tree in many homesteads, has become one of the villages most trusted allies in protecting crops. Behind the smiles and improved harvests lies a remarkable transformation driven by agroecological farming, where organic pesticides, indigenous seeds and sustainable farm...