In sub-optimal conditions in Southern Costa Rica (640 masl), vegetative growth of Coffea arabica cv. Costa Rica 95 was superior in agroforestry systems (AFS) with timber trees (Eucalyptus deglupta or Terminalia ivorensis) than under the leguminous tree Erythrina poeppigiana or in full sun, due to the microclimatic buffering effect of shade from timber trees. Coffee flowering occurred earlier and the number of flowers per productive node was higher in full sun than under shade, but the final number of fruits per productive nod was superior under E. deglupta or T. ivorensis, due to higher fruit drop in full sun or under E. poeppigiana (36 and 28%, respectively), compared to fruit drop under E. deglupta or T. ivorensis (15 and 16%, respectively). In AFS, distance of coffee plants to the shade tree had no significant effect on vegetative growth, flowering and fruiting intensity of the coffee. Branches higher up in the coffee canopy had higher growth, earlier flowering and higher fruit number per node. A higher initial increase in individual fruit weight was observed in full sun but the evolution of fruit development suggested a higher final individual fruit weight in shaded systems.