How Do Coffee Beans Grow?

Coffee has become a part of daily life everywhere; around the world you can grab a latte in Los Angeles or a flat white in Fiji and coffee is second only to water in its popularity. While water can be drunk with just a flip of the tap in much of the world, coffee is a lot more complicated. It takes years for a seed to be ready for harvesting and more time still for that seed to end up in a coffee machine. It is because of this lengthy process, involving thousands of hours of labour and hundreds of workers that the growing process of coffee must be understood and appreciated in the utmost. Not only that, but it’s really quite fascinating too.

The process begins with farming the plant and fostering its fruit, then using one of several methods such as the honey process to separate the beans from the fruit. We're here to answer the question, how do coffee beans grow?



I - The Coffee Plant

II - Coffee Bean Varieties

III - Coffee Bean Growth Stages

IV - Harvesting and Processing Methods

V - From Farm to Roastery

VI - FAQ's


The Coffee Plant

Coffee plants are classified as trees, small in stature, growing between two and eight metres tall. They are evergreen, usually with shiny leaves. They produce white flowers and red fruits known as cherries. The fragrance of the flowers is sweet, and the seeds of the fruit are what are harvested to be roasted as coffee beans.

Illustration of a coffee plant

Coffee trees do not grow in all climates. Ideal climate and conditions for coffee cultivation and when viewed on a map, the areas in which they are grown, known as the coffee belt, clearly mark the optimum conditions required for it to flourish. From this it’s clear that coffee grows in a minority of land mass, around 40%.

The Coffee Belt

Coffee Bean Varieties

There are two main types of coffee beans: Arabica and Robusta. Arabica plants prefer higher altitudes to grow as they like a cooler climate. This allows them to develop their fruit slowly. The plant relaxes between 18-23⁰C and so develops its fruit slower allowing higher concentrations of acids and sugars to be stored in the seed. The result is a denser seed packed with more complexity.

Robusta is a much hardier species than Arabica and can grow at lower altitudes where the temperatures are higher. Due to these conditions the plant spends less time developing the fruit but puts more effort into producing it in abundance, we find much fewer complex flavours and very low acidity.

Coffee Altitude showing what height Arabica and Robusta beans come from

While these are the two main varieties of the plant, there are other, unique variants. One of note would be Kapeng Barako, known more commonly as Barako coffee in the UK. It is grown in the Philippines and introduced during the Spanish colonisation of the islands.

While successful in its time, coffee rust (a fungus that destroys coffee plants) brought an end to much of its production. Interestingly there is a naturally occurring,

caffeine free variant called ‘coffea charrieriana’, found in Cameroon. These variants are not grown commonly for commercial use and require specific conditions to grow, like any specialty coffee. The ratios of mixing Arabica and Robusta, coupled with the varieties within themselves allow for an almost endless combination of flavours and profiles. Which is great news for anyone that loves the taste of coffee.

Coffee Bean Growth Stages

Illustration of the coffee bean growth stages

Like many plants, during the early stages of germination coffee trees are kept in nurseries to protect them from unexpected weather- such as extreme heat or rainfall. This period lasts between five and six months.  While the plant is fast growing, it is not quick to flower and will only start to bloom after three to four years. The plant grows green, waxy leaves at this time and begins to smell sweet, like jasmine.

The last element to appear are the cherries. They first form in tight, green bunches and after around 8 weeks of pollination, the cherries turn red (or in some varieties; orange, yellow or even pink). Withing these cherries are the coffee beans that the farmers want, and unlike a regular cherry, the seed in these takes up around 80% of the inside of the cherry. There isn’t much flesh to be found. That isn’t to say however, that there’s not much to these cherries once they have formed.

Between the skin and the beans are the mucilage and pectin layers. This sounds very technical but the key thing to remember about these layers is they contain most of the sugars vital to the fermentation process.

Harvesting and Processing Methods

When the season is right, the coffee plant will produce fruit. The fruit of the coffee plant is a little red cherry. Encased in the fruit and skin are, generally, two seeds. It is these seeds that we are interested in to make coffee. Processing the cherry is very important as how and when this is done can have a massive effect on the taste and quality of the coffee.

The three main methods are:

Dry/ Natural process

Removes the fruit by drying it out, the fruit is left on the seed whilst drying. This process will give fruity and sweet flavours to the final cup which can dominate the taste. The Dry process is the oldest and easiest way to process coffee as it does not require water.

Wet/ Washed process

Uses water to remove the fruit and clean the seed before drying. The coffee can show more delicate and complex flavours in the final cup.

Honey process

leaves a specific amount of fruit mucilage on the seed whilst drying, aiming to get the best of both processes.

Take a look at this chart that describes each stage of each processes.

A Chart showing the each stage of processing

From Farm to Roastery

The supply chain can be broken down as follows: growers, processors, intermediaries, exporters, suppliers, roasters, retailers, and customers. That’s a long list, but when it comes to transportation and distribution, we only need to look at a small section: the intermediaries, exporters, and suppliers. The intermediaries will connect other groups together (growers to exporters) and organise transport between links in the supply chain. They function as the logistics department of the operation.

The exporters do exactly that, they export. They buy coffee from multiple sources, countries and farms and then sell it on to other businesses, usually buying it in bulk and then selling it in smaller amounts, but often still wholesale. This is an important past of the coffee growing process because many countries that grow coffee rely on its exportation to make money. In Colombia for example, 90 percent of all the coffee grown there is exported. To carry out this role, companies need to have special licenses and permits which protects both the buyer and the farmer from exploitation. In recent years, the swell in demand for coffee has caused these exporters to need a greater knowledge of coffee to know where the best beans are being grown for speciality coffee. Demand for speciality coffee has grown in recent years and is defined as any coffee given a rating of eighty or above by an
SCAA coffee taster or a licenced Q Grader (CQI). Stokes is proud to roast and stock eight of these incredible coffees.

Suppliers are the ones who buy the coffee from exporters in the coffees country of origin and sell them to roasters in the UK. At Stokes we enter the supply chain here. Once the coffee is ready to import into the UK, Stokes does everything in house; we buy it in in its green bean form, roast it ourselves and package it in house to be sold in our own shop online, in our cafés and via wholesale too.

Once we have the beans in our roastery, it is time to transform them from green beans into aromatic delights. Coffee is commonly roasted in a drum roaster which works a little like a tumble dryer. There is a heat source that heats up the air around the drum. The heated air is drawn through the drum via a fan which transfers the heat to the beans via convection. The drum rotates, turning the coffee throughout the roast ensuring the beans get an even distribution of heat and that they do not just sit against the hot drum walls, although some of the heat is transferred this way through conduction, it is a combination of this movement and convection that ensures an even roast.

You can read our in depth blog here.


Can you grow coffee in the UK?

Unfortunately, no. the conditions in the UK are far from ideal and we sit too far north of the Coffee Belt to give the beans a fighting chance to flourish.

Are coffee cherries edible?

The short answer is yes, they are. After the beans have been removed the remaining pulp and skin is called cascara and it can be drunk as a fruit infusion like tea with a rather sweet taste. As for the cherries in their raw form they still can be eaten and they are still sweet however, given the small amount of flesh on them, it isn’t considered the nicest way to enjoy its flavour.


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