Coffee cultivation

Humanity has enjoyed coffee for almost a millennium. Today, it is more popular than ever. Although many coffee farmers adhere to traditional methods, cultivation, harvesting, transport, and trade have changed dramatically over time. Behind every espresso bean lies a complex, finely tuned process—a fascinating topic for anyone wanting to learn more about their favorite beverage.

The coffee plant's preferred climate

Most coffee plants thrive in tropical to subtropical climates with sufficient rainfall and consistent average temperatures between 18 and 26 degrees Celsius. The popular Arabica variety, in particular, prefers higher altitudes – hence the name. Highland coffeeAlthough pests are easier to control at higher altitudes, the costs for cultivation, harvesting, and transport increase significantly. This is why Arabica beans are more expensive than Robusta coffees grown in lowland areas.

In the so-called "coffee belt" of the tropics, between 23 degrees north and 25 degrees south latitude, lie over 80 coffee-producing countries. Diverse geographical conditions and traditions give rise to an enormous variety – from Jamaica's Blue Mountain and Indonesia's Kopi Luwak to monsoon and Himalayan coffee. Each variety is the distinctive product of its specific environment and centuries of experience.

Coffee plantations

The journey of coffee begins with the cultivation of the coffee plant. Selected green coffee beans are sown in nutrient-rich soil in so-called "nurseries" and regularly watered. After a few days, the seedlings, called "soldiers," sprout. A year later, the young plants are transplanted to large plantations.

For particularly pure propagation, seedlings are used, which are plant parts from mature bushes. Coffee plants are often combined with so-called "coffee mamas"—crops such as banana or pepper trees. These provide shade and promote a healthy mixed crop.

After three to four years, the plants are ready for harvest for the first time, reaching their maximum yield after about ten years. Since coffee plants can grow up to ten meters tall, they are regularly pruned to facilitate harvesting by hand. After about twenty years, their fertility declines, and they are replaced with new plants.

The coffee harvest

Because coffee plants grow in tropical regions with a largely constant climate, the seasons there hardly differ. Flowering and fruit development depend not on the season, but on rainfall. Prolonged droughts can therefore have catastrophic consequences and quickly affect the world market price.

The coffee plant begins to flower approximately two to three weeks after a heavy rain – regardless of how often it rains during the year. Modern farms sometimes use artificial irrigation to achieve more consistent yields. Since ripe cherries develop between six and eleven months after flowering, a single bush usually contains fruit at different stages of ripeness. High-quality harvests are therefore only possible using the so-called "picking" method.

Picking and stripping

At the PickingIn this method, the ripe, red coffee cherries are picked by hand. Workers select only the best fruits and leave unripe cherries and blossoms on the bush until they ripen. This elaborate but meticulous method produces particularly high-quality coffees and simultaneously creates many jobs. It is primarily used for Arabica cultivation in mountainous regions where machinery is hardly feasible. Up to one hundred productive plants must be harvested to produce a 60-kg sack of green coffee.

In the so-called Stripping In contrast, once or twice a year all the cherries – ripe and unripe – are stripped from the bush at once. Although this method also results in the harvesting of inferior beans, it is significantly faster and more cost-effective.

Mechanical harvesting

Harvesting machines are increasingly being used, especially in Robusta cultivation in flat regions. Similar to stripping, all the fruits are harvested simultaneously and later sorted. For this to work, the plants must grow in rows and not exceed a certain height.

Rotating brushes on both sides, mounted vertically, strip the coffee cherries from the branches and let them fall to the ground. Older machines require clean, unplanted ground for collecting the fruit, which often necessitates heavy herbicide use. Newer models collect the cherries directly in hoppers. However, because the plants can be damaged by mechanical harvesting and many growing areas are difficult to access, this method is only used to a limited extent.

From coffee cherry to bean

After harvesting, the coffee cherries are quickly transported to the farm to prevent premature fermentation. There, impurities and damaged fruit are sorted out before the pulp is removed and the beans are dried.

There are two common processing methods – dry and wet. Only after this step are the beans packaged, shipped, and delivered to roasters. For this, the coffee usually leaves its country of origin and embarks on a long journey across the oceans. Thus, every cup of espresso tells a fascinating story!

The dry processing

In the so-called NaturalIn the sun-drying method, freshly harvested coffee cherries are spread out on flat, clean surfaces and dried in the sun – a method that is hardly feasible in humid regions. To prevent mold growth, the cherries are turned regularly. In bad weather, drying ovens assist the process. After three to six days, the pulp is mechanically removed, and the beans – some of which still have their parchment skin attached – are then ready for roasting.

During drying, some of the fruit sugar is transferred into the bean through osmosis. This gives naturally processed coffee its characteristic sweetness and makes it particularly well-suited for espresso blends.

The wet processing

At the washedIn this method, the coffee cherries are separated from the pulp after harvesting in a pulping drum. The beans, covered with a mucilage layer and called parchment, then pass through water channels into fermentation tanks. Defective cherries float to the top and are removed.

During fermentation, the parchment and silverskin dissolve, allowing it to be easily washed off. The clean beans are then dried – naturally or mechanically. Depending on the thoroughness of the drying process, a distinction is made between... pulped natural, semi washed and fully washed.