Wake up and sell more coffee. Small farmers in Africa need to produce more. Happily that is easier than it sounds

ON A hillside about an hour’s drive north of Nairobi, Kenya’s capital, is a visible demonstration of the difference between the miserable reality of smallholder farming in Africa and what it could be. On one side of the steep terraces stand verdant bushes, their stems heavy with plump coffee beans. A few feet away are sickly ones, their sparse leaves spotted with disease and streaked with yellow because of a lack of fertiliser.