Coffee Tree: How the Coffea Plant Goes From Seed to Bean

A coffee tree is an evergreen of the coffee family, Rubiaceae, and every coffee bean you have ever brewed is one of its seeds. Following a coffee plant from seed to bean means following a cycle measured in years before the first crop, and in months for every cherry after that.

One clarification first, because search engines muddle it: the coffee tree here is not the Kentucky coffeetree (Gymnocladus dioicus), an unrelated legume of the bean family, Fabaceae, whose raw seeds are toxic. Everything below concerns Coffea, the genus that gives us the drink.

What kind of plant is coffee?

Botanists describe the coffee plant as a shrub that can grow to the size of a small tree. NC State Extension calls Coffea arabica a small, broadleaf evergreen shrub or small tree in the coffee family, and the research organization CIRAD puts it just as plainly: "Coffee trees are evergreen shrubs of the family Rubiaceae." So "coffee tree" and "coffee bush" are both fair names for the same plant; which one fits depends partly on size and pruning.

A large genus, mostly under threat

Coffea is a larger genus than most coffee drinkers imagine. A 2019 assessment by Aaron Davis and colleagues, published in Science Advances, counted 124 wild coffee species. That number is not fixed: CIRAD's own page still gives a figure of close to 80 species, and the count shifts with the date of the study and with how botanists draw the edges of the genus.

The same 2019 assessment delivered a sobering result. Applying the IUCN Red List criteria to every wild species, the authors found that "at least 60% of all coffee species are threatened with extinction". Most of the genus, in other words, is wild and at risk.

Two species carry the crop

Of all those species, the coffee trade rests on two: Coffea arabica and Coffea canephora, better known as robusta. How they differ in the field and in the cup is a subject of its own, covered in our guide to arabica vs robusta. Here it is enough to know that the two behave differently at several points in the life cycle below, from pollination to ripening time. Each species also deserves a portrait of its own: an arabica profile and a robusta profile.

Wild arabica comes from Ethiopia. A 2012 study in PLOS ONE reports that "The largest and most diverse populations of indigenous (wild) Arabica occur in the highlands of south-western Ethiopia". The story of how the drink emerged from those forests belongs to where coffee originated, and the country's growing areas today are mapped in our guide to Ethiopian coffee regions.

What does a coffee tree look like?

Height: tall in the wild, kept short on farms

Published heights for the coffee tree vary more than you might expect, so each figure below comes with its source. NC State lists about 1.8 to 4.6 m (6 to 15 ft) for arabica. CIRAD says arabica can grow to 5 to 6 m (about 16 to 20 ft) and robusta to 10 to 12 m (about 33 to 39 ft). The University of Florida's IFAS extension service goes further, noting that coffee trees can reach about 15 m (50 ft).

On farms, few trees get anywhere near those heights. Growers prune them far below their wild height, usually to around 2 m (about 6.6 ft); CIRAD gives a slightly wider range of 2 to 3 m (about 6.6 to 9.8 ft).

Leaves

The leaves are the plant's most constant feature. NC State describes them as glabrous (hairless), glossy and dark green, with prominent veins and wavy margins; UF/IFAS adds that they are ovate, with rippled edges. If you have ever seen a coffee tree in a botanical garden, that glossy, slightly crinkled leaf is usually what gives it away.

Flowering: rain, scent and a few short days

Rain sets it off

Coffee does not flower on a calendar date. Coffee Review describes "a broad season of flowering provoked by rain", and Kauai Coffee, a grower, notes that the flowers generally appear a few days to a few weeks after significant rainfall.

UF/IFAS notes that "the white, five-petaled flowers appear in clusters along the stem", and CIRAD calls them very strongly scented. What the scent resembles depends on who is smelling: it is often compared to jasmine (NC State), while Kauai Coffee finds it closer to citrus blossom, sweet and fairly mild.

Blossoms that last a few days at most

The show does not last. Coffee Review writes that "three or four days later, the petals are strewn on the ground", while Kauai Coffee says the flowers are "only open for a day or two before withering". The sources agree that each blossom is short-lived; they differ on the count, so a few days at most is the honest summary.

Pollination

Arabica flowers can pollinate themselves: in UF/IFAS's words, they are "self-fertile, which means they don’t require cross-pollination to bear fruit". Robusta works the other way. UF/IFAS says its flowers "do require cross-pollination to bear fruit", and a 2003 study of bee pollination by Klein and colleagues, in the American Journal of Botany, describes Coffea canephora as self-sterile.

One flowering or two

The rhythm of flowering sets the rhythm of harvest. The National Coffee Association (NCA) notes that in most coffee-growing regions there is one major harvest each year, and that in countries like Colombia, which have two flowerings annually, there is a main crop and a secondary crop. Where rain falls sporadically all year, as in parts of Sumatra, Coffee Review observes that "blossoms, unripe fruit, and ripe fruit may cohabit the trees".

The coffee cherry

From flower to ripe fruit

Once a flower is pollinated, the fruit takes months to form, and the figures vary. For arabica, Coffee Review and Kauai Coffee both give about six to seven months. CIRAD gives six to eight months in one passage and, in its paragraph on arabica cultivation, six to ten months for fruit set. A 2025 review of arabica flowering and fruiting by Unigarro and colleagues, in the journal Plants, puts the average at 220 to 243 days from flowering to ripe fruit (roughly seven to eight months), with a spread of 180 to 330 days depending on the site's temperature and humidity. A fair reading is around seven to eight months for arabica, and anywhere from about six to ten depending on climate. Robusta takes longer: eight to twelve months, according to CIRAD.

When ripe, the cherries are, in Coffee Review's description, "oval, about the size of your little finger". NC State follows their color from green through yellow and light red to deep red, and Coffee Review adds the exception: "Most varieties turn bright red when ripe; a few varieties ripen to a golden yellow." If you want to know what a coffee variety is in the first place, our profiles of Typica and Bourbon are a good place to start.

Because cherries do not all ripen at once, selective picking means repeated passes. The NCA describes pickers who rotate among the trees every 8 to 10 days, picking only the ripe cherries by hand. That is one harvesting method among several, not the only one.

Inside the cherry, layer by layer

Peel a coffee cherry and you work through a series of layers before you reach anything that looks like coffee. Food scientists writing in Foods in 2021 (Bastian and colleagues) summarize it this way: "Coffee cherry fruit consists of an exocarp, mesocarp, endocarp, silver skin, and endosperm (bean)." From the outside in:

• Exocarp: the skin, red or yellow when ripe.
• Mesocarp: the sweet pulp. Bastian and colleagues give it a thickness of around 0.5 to 2 mm and divide it into external and internal parts.
• Endocarp, or parchment: in the words of Kaʻū Coffee Mill, "The endocarp, or parchment, is the innermost layer of the pericarp and is the hull that envelops the coffee bean." CIRAD describes it as a pale yellow sheath around each seed. Bastian and colleagues put it at around 0.15 mm.
• Silverskin: a thin skin on the outside of the seed, beneath the parchment. Only part of it is still on the green bean, and Kaʻū notes that those remnants come off as chaff during roasting.
• Endosperm: the seed itself, the part we roast.

The ordered list and the thickness figures come from that one paper; Kaʻū describes each layer separately in a way that agrees with it.

The vocabulary is a frequent source of confusion, so it is worth flagging. Kaʻū uses "mucilage" as another name for the mesocarp, while some coffee educators count mucilage as a separate layer; Kaʻū also lists perisperm and spermoderm as other names for the silverskin. If two guides seem to disagree on how many layers a cherry has, they are often naming the same tissue in different ways.

Two seeds, side by side (usually)

Inside the parchment, a cherry normally holds two seeds. CIRAD describes "two oval seeds, side by side", and UF/IFAS notes that "Within the fruits are two seeds that look just like the whole coffee beans". Packed together in one fruit, the two seeds grow face to face, flat against each other.

Now and then a cherry develops only one. Coffee Review's Kenneth Davids, writing in 2003, describes a peaberry as a cherry that "develops a single oval bean rather than the usual pair of flat-sided beans". Both he and Kaʻū Coffee Mill put peaberries at roughly 5 % of the crop.

The bean is a seed

Here is the fact that ties the whole cycle together. As the NCA puts it, "the seeds of coffee cherries are the same thing as coffee beans", and NC State notes that the seeds are what are usually dried, roasted and ground to make coffee. The bean in your grinder is that seed, stopped in its tracks by drying and roasting.

From seed to seedling

Most coffee trees start life in a nursery. According to the NCA, "Coffee seedlings are generally planted in large beds in shaded nurseries." An FAO manual written for growers in Laos, and so for one country's conditions, gives a sense of the pace: it may take 30 to 50 days before shoots appear, depending heavily on soil temperature, and the seed loses its viability within about three months.

From seedling to first crop

Patience is part of the plant's nature. The NCA says it takes approximately three to four years for the trees to bear fruit, depending on the variety. Coffee Review gives about three years to bear and six to reach maturity for a tree grown from seed, and CIRAD says arabica begins to bear after two to three years. NC State's three to four years refers to the first blooms rather than the first crop. Put together: usually three to four years from seed, with some sources saying two to three.

Where the numbers disagree

Coffee botany is full of ranges, and most disagreements seem to come down to species, climate, or what exactly is being measured.

None of these ranges is necessarily wrong: they come from different species, places and definitions, which is a good reason to be wary of any single number quoted without its source.

From picked cherry to green bean

The cycle ends where the coffee trade begins. Once the ripe cherry is picked, the skin, pulp and parchment are stripped away by one processing method or another (a subject for another article), and what remains is the green bean: the seed, dried and ready to travel. From there, you can follow it into the roaster with our guide on how to roast coffee at home. To name what you find in the cup, try the coffee flavor wheel. And for everything else on the plant and its varieties, browse coffee knowledge.