Coffee Flowers Can Be Pink?! What's the Difference Between Pink and White Coffee Flowers?

For millions of coffee farmers around the world, the bloom of fragrant white flower clusters on the coffee trees signals that harvest is not far off. The more abundant and dense the petals, the more cherries a farmer can expect to bring in.

By tradition, coffee flowers are an elegant, simple pure white, made up of 5-6 petals arranged in clusters along slender branches. Every February and March, the coffee trees near FrontStreet Coffee's storefront bloom in scattered bursts, releasing fragrances similar to other white flowers such as jasmine, magnolia, and thyme, and filling the air with something fresh and uplifting.

Did you know, though, that in rare cases coffee trees can also produce pink flowers? What causes this variation?

The Science Behind Pink Coffee Flowers

In an interview with Perfect Daily Grind, Oliveiro Guerreiro Filho, a genetics and plant breeding expert from the Agronomic Institute of Campinas in Brazil, explained that this rare pink flower phenomenon occurs mainly in two kinds of coffee varieties.

One is caused by natural genetic variation in the coffee plant. Research has found that certain varieties are more likely to produce pink flowers, such as the naturally low-caffeine variety Coffea racemosa and its hybrid offspring Aramosa.

Coffea racemosa, also known as racemose coffee, is native to southern Africa and is one of the oldest coffee varieties, with a naturally very low caffeine content. It was first introduced to Brazil in 1954. Later, agricultural researchers at Campinas crossed it with Arabica and, through selection, obtained the Aramosa variety, which today is grown only on a few small estates in Brazil.

While regular Arabica beans typically contain about 1.2%-1.6% caffeine, Aramosa coffee contains only 0.7%. This low-caffeine trait reduces the plant's resistance to pests, so the variety must be grown at higher altitudes. During the flowering season, Aramosa trees produce rose-pink flowers, and their mature cherries take on a purplish-red color.

The Purpurascens Variety

The other type of coffee tree that produces pink flower clusters is called Purpurascens, caused by spontaneous mutations in the plant's chromosomal DNA sequence. Gene expression determines the color of the entire plant: Purpurascens trees have purple young leaves, new stems, and stipules, while their flowers display a beautiful pink. Researchers also note that Purpurascens mutant trees typically yield less and are more vulnerable to pest attacks.

In 2009, for example, the owner of El Socorro estate in Guatemala spotted Purpurascens plants with purple leaves and pink flowers among their Maracaturra seedlings, and immediately separated them for cultivation. After harvesting, they found that this mutant variety delivered excellent cupping results, with fruit acidity reminiscent of black currant and ripe plums. They went on to use grafting for commercial cultivation, and the result later won multiple Guatemala Cup of Excellence awards.

The Future of Pink Coffee Flowers

Most coffee growers may never have seen pink flowers on a coffee tree, and may never encounter them. Even so, as producers and researchers continue to develop hybrid varieties, we may well see more coffee plants blooming pink in the not-too-distant future.

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FrontStreet Coffee Recommendation

The story of a flower color set by genetics is a reminder of how much variety shapes what ends up in the cup, and Brazil, home to the Campinas institute behind Aramosa, offers some classic examples. FrontStreet Coffee Brazil Cerrado Red Bourbon is a classic Brazilian single origin, a red Bourbon from the well-known Cerrado region, medium roasted to bring out creamy peanut, toasted bread, caramel, and hazelnut aromas with a round, low-acid body and only a faint bitterness, suited to pour-over, moka pot, espresso SOE, siphon, or French press.

FrontStreet Coffee Brazil Queen Estate, by contrast, is a rare yellow Bourbon grown in Mogiana on fertile red volcanic soil. It has cleaner fruit than red Bourbon and shows a sugarcane sweetness unique to the region, along with fruit and chocolate notes, across pour-over, moka pot, and home espresso machine.