Growing coffee is no simple matter; fertile soil and expert hands are not enough; specific climatic conditions are essential for the proper growth of the plant and fruit. In this article, we discuss the ideal environmental conditions for growing coffee and how they influence the characteristics of the final beverage.
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TEMPERATURE:
Temperature significantly affects the growth of coffee:
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Arabica coffee: prefers a temperate climate with temperatures between 15°C and 24°C. This variety does not respond well to high temperatures, which can lead to a reduction in acidity and elegance.
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Robusta Coffee: it is the most resistant variety and does well at higher temperatures, between 24°C and 30°C.
For optimal plant growth, both Arabica and Robusta varieties require minimal temperature fluctuations between day and night, and there should be no marked difference between the four seasons. Mild temperatures favor a slow but steady ripening of the cherries, allowing for the development of greater aromatic complexity. Excessively high temperatures accelerate growth and produce a less aromatic coffee with a flatter, more bitter flavor. Because of this need for temperature stability, all coffee, both Arabica and Robusta, is grown in a zone known as the intertropical zone, between the Tropic of Cancer and the Tropic of Capricorn.
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ALTITUDE:
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Arabica grows between 600 and 2,000 meters above sea level.
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Robusta is grown at lower altitudes between 200 and 800 m above sea level.
Altitude slows the fruit's ripening process, resulting in the development of complex sugars that make the coffee sweeter and more aromatic. The higher the coffee is grown, the more floral and fruity notes it will have, along with a subtle acidity typical of specialty coffees. Conversely, lower altitudes produce coffees that grow more quickly, are typically more bitter, fuller-bodied, less aromatic, and less complex.
3. RAIN AND HUMIDITY
A prerequisite for coffee growth is abundant rainfall, which must be well distributed throughout the year. The ideal annual rainfall is 1,200–2,200 mm. The dry season is also important, allowing for optimal flowering and harvesting conditions.
A proper balance between rain and sun is essential for synchronizing flowering and fruit ripening. Excess rainfall can cause mold and unwanted fermentation, negatively impacting flavor. Conversely, prolonged drought can stress the plant, reduce yield, and produce darker, more bitter berries.
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SOIL
The required coffee soils must have some characteristics:
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good drainage to avoid water stagnation.
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rich in organic matter
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A slightly acidic pH, between 6 and 6.5.
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great depth so that the roots can settle in better
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good porosity which guarantees the supply of oxygen to the root system.
Soil provides essential nutrients and influences coffee's sensory characteristics. Volcanic soils, rich in minerals, are known for giving coffee liveliness, body, and complex aromas. Volcanic zones are extremely fertile, producing some of the world's finest coffees. Soil lacking in minerals or waterlogged soil can stress the plant, resulting in uneven beans with flavor defects.
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SOLAR RADIATION AND SHADING
Excessive, direct, and intense sun exposure can subject the plant to photooxidative stress, which can cause leaf necrosis and reduced photosynthesis efficiency. Medium-to-large trees are commonly planted in coffee plantations to provide shade, mitigate the climate, and improve moisture retention. It's important that this shade is not excessive, as it can slow photosynthesis, excessively increase humidity, and cause fungal diseases.
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EXTREME CLIMATE EVENTS
Extreme weather events such as heat waves, droughts, torrential rains, and severe frosts are becoming increasingly common due to climate change. These events can have serious repercussions on coffee plants; they reduce crop yields, alter plant phenology, and the timing of flowering.
Coffee production is closely linked to specific climatic factors that must be precisely monitored and managed with targeted agricultural practices. Looking to the future and a global context characterized by significant climate instability and a growing demand for high-quality coffee, it will be essential to invest in agroclimatic research, genetic improvement, and territorial adaptation techniques. Only by implementing an integrated approach based on scientific data and sustainable innovation will it be possible to protect the coffee supply chain and preserve its economic, cultural, and social value.