Coffee can be harvested all year round. However, harvesting times vary by growing area. While harvesting can take place any time of year in growing areas close to the equator, it takes place between July and December in areas to the north, and between April and August to the south. Harvesting can take up to 12 weeks, because even cherries on a single stem ripen at different rates. Harvesting methods include picking, stripping, mechanical harvesting, late picking and selective picking.
Picking, or hand picking, is the most expensive and traditional harvesting method and, nowadays, is only used for premium coffee roasts. It is an extremely time and labour intensive method as only ripe cherries are picked by hand. As a result of differing ripening times, selective hand picking is repeated every 8 to 10 days. During the final harvest, pickers separate ripe coffee cherries from over-ripe ones, which must also be removed from the trees. After picking, the beans are sorted by hand again to ensure only optimally ripe beans are processed. The result is a homogenous harvest of the highest quality coffee.
Stripping is a fast and considerably cheaper harvesting method. The branches are manually stripped at the optimal time, i.e. when the highest number of ripe cherries are on the coffee plant. But this process does not take the ripeness of individual cherries into account. The stripped cherries fall onto a sheet on the ground along with leaves and small twigs. The leaves and twigs are then removed by hand and the cherries put into sacks. Comb-like equipment is now also used to an extent in stripping for the harvest of coffee cherries. However, the use of such a tool entails the danger of damaging the coffee plant and, in turn, reducing the yield.
Mechanical harvesting involves heavy harvesting machinery used on large plantations. However, this requires a flat harvesting area and a large gap between individual plants. The harvesting machines shake the coffee cherries off the plants through vibration and then throw them onto the conveyor belt located inside the machine. This method is fast, inexpensive and ensures independence from harvesting workers. However, a homogenous harvesting result cannot be achieved and the coffee plants are damaged. Consequently, the cherries must be very carefully processed after harvesting: damaged cherries must be removed and ripe cherries separated from unripe and over-ripe ones. Thanks to post-processing, these machines can be used for both mass production and high quality coffees.
Late harvesting involves purposefully inducing changes in flavour. The coffee cherries are left on the coffee plant after attaining optimal ripeness. As a result, the coffee cherries are affected by a desired noble rot, which lends the coffee beans a certain sweetness.
Selective picking is a very special, very seldom used harvesting method. Different members of the animal kingdom – e.g. the jacu bird or the viverridae – eat the ripest coffee cherries. However, because only the fruit's pulp can be digested, the beans are discarded. The beans are wet fermented by special enzymes in the viverridae's intestines, changing their flavour characteristics. However, the coffee's special taste is more closely linked to the animal's "personal mix", because it does not just eat cherries from a single coffee plant. Rather, it picks and chooses from different plants, depending on its personal preference, as it were. Plantation workers collect the excrement for further processing. The effort and extravagance required to produce this coffee make it the most expensive of all, with prices of up to 1,200 euros per kilo.