A Beginner's Guide to Coffee
In this third installment of our Coffee 101 series, we examine how coffee is grown. The world's coffees are grown and produced in 70 countries situated along the equatorial belt between the Tropic of Cancer and the Tropic of Capricorn.
Much like wine, where a particular coffee comes from determines its characteristics. A coffee's terroir - a sense of the place from which it comes - is determined by a variety of conditions that are unique to each location.
Factors including topography, soil composition, and climate, can all influence the characteristics of coffee beans. Even coffee plants growing in the same region but in slightly different conditions, such as opposing slopes within the same mountain range, can yield distinct flavor profiles.
Successfully growing coffee on a commercial scale is a very challenging endeavor. But despite all the difficulties and uncertainties, a bountiful crop yielding coffee beans with exquisite characteristics makes it all worthwhile. Keep reading to learn more about how coffee is grown and what makes it so challenging year in and year out.
Previously: Part One - What Is Coffee?
Previously: Part Two - Where Does Coffee Come From?
How Is Coffee Grown?
The unmistakable aroma and deeply satisfying flavor of coffee make it easy to forget that before coffee can be brewed and enjoyed, it must first be planted, grown, cultivated, harvested, and processed.
Each bean's journey from seed to cup is long and arduous. Only under the right circumstances will a crop yield a coffee's intended characteristics.
As we learned in Part Two - Where Does Coffee Come From, coffee grows within a wide strip encircling the earth lying between the Tropic of Cancer to the north and the Tropic of Capricorn to the south. From this, we can gather that a tropical climate is vital to the growth of the Coffea plant.
But as we are about to see, there is far more to growing coffee than warm, sunny weather. In fact, there are many pieces to the puzzle and each has to fit just right in order for coffee to thrive.
Here are the basic conditions that coffee needs for sustainable growth. (Note: this article focuses on arabica coffee.)
Altitude
The world's coffees come from tropical regions lying around the earth's equator. But this does not mean that coffee plants can grow anywhere within the planet's midsection.
As a general rule, coffee, particularly arabicas, grow best at altitudes above 1,800 feet (approximately 500 meters).
The ideal altitude for coffee growth varies within the coffee belt and largely depends on the distance of a particular growing region from the equator. For instance:
Right around the equator (0° - 10° north and south latitude), the ideal altitude for growing coffee is between 3,600 to 6,300 feet (roughly 1,100 to 1,900 meters) above sea level.
Further north and south of the equator (i.e., around 15° north and south latitude) the ideal altitude is typically between 1,800 to 3,600 feet (500 to 1,100 meters).
Microclimates within a particular area can significantly affect the altitude at which a specific coffee will thrive and produce desirable characteristics.
Precipitation
Another key condition for coffee growth is precipitation. Water, in the form of rainfall, is crucial for delivering vital nutrients and life-sustaining elements to the root systems of coffee plants.
Water is the lifeblood for virtually all living things on the planet, and for the coffee plant, proper amounts of precipitation can be the difference between a bountiful crop and a disappointing one.
The amount of precipitation needed to sustain coffee plants depends on the region and other circumstances.
Generally speaking, established coffee plants require at least 60" (approximately 1,500 mm) of rainfall each year
Certain varieties need 90" (approximately 2,300 mm) of annual precipitation
Ideally, most coffee plant varieties prefer long, sustained periods of consistent precipitation followed by shorter dry periods to promote flowering and fruit (cherry) development.
Unstable weather patterns resulting in inconsistent annual precipitation amounts can wreak havoc on coffee crops. In particular, nothing can result in more widespread and long-standing damage to coffee plants than drought conditions.
Soil Composition
Just like any plant life, arabica coffee prefers a certain soil composition and thrives when these conditions are met. These requirements can vary from location to location. Ideal soil conditions also depend on the particular coffee variety being grown.
As far as soil composition, these are a few specific requirements for coffee plants:
Nitrogen - this vital nutrient ensures healthy plant functions including photosynthesis and promotes growth
Phosphorus - promotes the healthy development of the plant's root system, buds, and flowers
Potassium - encourages the proper development and ripening of the fruit (i.e., the coffee cherry)
Other essential nutrients include zinc and magnesium
As far as pH, arabica coffee does well in soil that is slightly acidic to near neutral (a range of 4.0 to 7.0 on a pH scale)
Many coffee-growing regions are situated in areas where rich volcanic soils provide ample amounts of minerals to sustain coffee plants as seedlings through their mature, fruit-bearing years.
Sunlight and Shade
A term you frequently hear on the topic of plants and sunlight is photosynthesis - the process by which plants utilize natural light from the sun to convert carbon dioxide and water into life-sustaining energy. It stands to reason that the more sunlight that is available, the better the results.
But in the case of arabica coffee, this is not necessarily true.
Arabica coffees grown around the world are descended from the original species of Coffea Arabica that grew wild in Ethiopia.
In its native land, coffee was an understory plant, meaning that it thrived underneath the forest canopy, shielded from direct sunlight.
As such, arabica coffee has been genetically "trained" to thrive in partial or indirect sun and many species grown around the world today have retained this trait.
By mimicking an understory environment, the availability of shade trees surrounding coffee plants can produce exquisite coffees with characteristics presented in the way that nature intended.
Temperature
Another growing condition directly affecting the health and productivity of coffee plants is temperature. The so-called coffee belt lies in the earth's midsection between the Tropic of Cancer and the Tropic of Capricorn.
But within these tropical zones, arabica coffee grows on mountainous terrain at altitudes of 1,800 feet or higher. As such, coffee plants are accustomed to moderate temperatures and do not fare well in extreme heat or cold. Here are some of the ways that coffee growth is affected by temperature:
The ideal temperature range for arabica coffee is 59° F to 75° F (15° C to 24° C)
On the cold end of the temperature scale, frost (i.e., temperatures at 32° F/0° C) can permanently damage a coffee plant's leaves and impair the development of the fruit
By the same token, extremely high temperatures can likewise cripple a coffee plant's growth and diminish its ability to bear harvestable fruit
As with so many of the factors influencing coffee growth, extreme temperatures can disrupt the normal life cycle of the plant and sustained exposure can produce long-term problems.
Balance Is Key
Growing coffee on a commercial scale is an endeavor characterized by its uncertainty. There are many variables to contend with, not the least of which, is Mother Nature herself.
Uncooperative weather patterns such as a prolonged drought, or even a single natural event like a severe frost, can ruin an entire crop.
For coffee to truly thrive and produce beans reaching their full flavor potential, the growth factors described above must be favorable and aligned with each other.
While this may sound like the odds are stacked against it year in and year out, more often than not, coffee has proven its resiliency and produced beans that have satisfied the consumption needs of millions of coffee drinkers around the world.
A Few Words About Global Warming and Coffee
Among the most pressing issues in the world today are the increasingly alarming effects of climate change.
Global warming has been linked to dramatically changing weather patterns around the globe. Catastrophic natural events and sustained abnormalities have disrupted the growth cycles of many vital crops.
According to the National Oceanic and Atmospheric Administration (NOAA), within a few decades, climate change can greatly impact the world's production of coffee, particularly arabica beans. For instance:
By the year 2050, the areas within the coffee belt that are suitable for growing coffee may shrink considerably due to global warming
Even an increase of just a few degrees in average temperature can disrupt the coffee plant's natural growth cycle, stunting growth and resulting in underdeveloped or over-ripened fruit
Rising temperatures may force growers and producers to relocate their operations to higher (and thus, cooler) elevations, which in turn will create greater challenges and raise production costs
Global warming is also linked to worsening pest and disease problems affecting coffee plants around the world
As the old saying goes, nature always finds a way. But nature has never had to contend with the far-reaching impacts of global warming like it is now. What happens to global coffee production in the short-term, and in the decades to come, remains to be seen.
Final Thoughts
For a coffee plant to produce a bountiful yield of flavorful coffee beans, it needs the right balance of altitude, precipitation, soil composition, sunlight, shade, and temperature.
In many ways, growing coffee is a labor of love. Once the fruit matures, however, the true work of coffee production begins. Keep reading to learn how coffee is harvested and processed for export.