Coffee

Puerto Rican coffee is the coffee served at the Vatican.  Puerto Rican coffee was quite popular in Europe in the 19th century, until Hurricane San Ciriaco killed 3500 people on the island in 1899 and destroyed essentially all agriculture extant.

Shade-grown coffee is organically grown and environmentally extremely friendly; coffee bushes naturally prefer shade.  But shade-grown coffee consists of bushes scattered through the understudy of tropical rainforest.  It must be harvested by hand, so labor-intensive a process that it can only be done in the Third World for any price bearable for mass export.  This is the reason that Puerto Rican coffee never managed to rebuild after 1899.  Recent price supports by the government have only supported a switch to sun-grown coffee - an effort that has not been successful.

The technology isn't here yet, but robotic management of coffee (and other plants) in the forest understudy could possibly be cheaper than human labor, perhaps bringing Puerto Rican shade-grown coffee into a bearable price range - Puerto Rico does have a fairly well-developed technical sector that could provide maintenance and operating labor for robotic harvesters.

Longer-term, but in the end all the real money is from use of the land.