When Angela Leony visited the town of Lençóis in northeastern Brazil 18 years ago, she was unable to conceive. Yearning for a child, she went to see Dona Senhorinha, an elder healer.

Senhorinha told Leony the problem might be solved by drinking tea made from Estradeira-vermelha, a native pea plant with a bright red flower known for its ability to start the menstrual cycle and facilitate pregnancy.