Where Do You Grow Coffee Beans Like Kenya's SL28?

SL28 was selected in Kenya in the 1930s from a drought-resistant Tanganyika variety. Growers plant it on highland slopes above 1,600 meters, mainly in Nyeri, Kirinyaga and Murang'a. Where do you grow coffee beans for the classic washed cup? These central Kenyan counties, with their red volcanic soil and cool nights, give SL28 its blackcurrant acidity.

The washed process removes the cherry skin and mucilage before drying on raised beds. The result is a bright, clean cup with blackcurrant, tomato and citrus notes. A coffee cookie cup can pair well with this profile, since the crunchy shell contrasts the tea-like body. SL28 remains popular despite low yield and disease pressure.

Among African coffee-producing countries, Kenya stands out with its signature dark plum acidity and bright fruity notes. The unsung heroes behind this flavor are the SL28 and SL34 varieties bred by Scott Laboratories in the last century. From Front Street's perspective, this article traces SL28's discovery and breeding history, its Bourbon genetic origins and flavor advantages, as well as its shortcomings in disease resistance. At the same time, using a washed bean example from the Asali Processing Plant in Kenya's Thika region, it shares the brewing performance and tasting impressions of this Front Street Kenya · Cherry Tomato, helping you understand how variety, terroir, and processing method together shape a cup of Kenyan coffee.

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Different grape varieties produce wines with vastly different styles, and the same is true for coffee—bean variety is often one of the core variables determining the flavor direction in the cup. Panama T2722 Geisha is clear proof of this, winning countless attention with its white floral aroma and citrus notes.

Today Front Street wants to talk about another equally standout star variety: SL28 from Kenya. The reason Kenyan coffee can present its classic dark plum aroma and bright acidity is largely thanks to this variety.

SL28 SL28 is Kenya's most recognizable representative variety, a direct descendant of the Bourbon family, selected and bred in Kenya in the early twentieth century. The institution leading this work was Scott Laboratories, with SL being the abbreviation of Scott Laboratories, and 28 representing the variety's experimental number at the time.

In the 1930s, the Kenyan government entrusted coffee breeding research to Scott Laboratories, with the goal of identifying varieties that could adapt to the local terroir, have commercial value, and be promoted on a large scale. Between 1935 and 1939, the laboratory collected 42 varieties from different producing regions and systematically evaluated them for yield, quality, drought resistance, and disease resistance, with several varieties ultimately standing out. Among the most famous are SL28 and SL34, which remain the two pillars of "Kenyan flavor" to this day.

According to information reviewed by Front Street, in 1931 a senior official at Scott Laboratories discovered in the Munduli area of northeastern Tanganyika (present-day Tanzania) a small-seeded coffee that appeared tolerant to drought, disease, and pests, and subsequently brought it back to Kenya for research, where its drought resistance was verified. In 1935, this variety formally entered the breeding process—it was SL28.

In addition to drought resistance, SL28 also offered considerable yield, excellent flavor, and bright acidity. Because of this, after Kenyan authorities released and promoted it, it quickly became a highly sought-after rising star. It was first introduced to Uganda, and later even Central American producing countries joined the ranks of cultivation, showing just how popular it was. However, SL28 is not without shortcomings. Like SL34, it does not have disease resistance and is susceptible to various coffee diseases.

Research also shows that SL28 belongs to the Bourbon genetic group, meaning it evolved from Bourbon, so its bean shape is also round and short like Bourbon, making it quite easy to identify.

Today most Kenyan coffee is produced as a blend of SL28 and SL34. Because the two differ noticeably in bean appearance (SL34 is a Typica variant, slender and oval-shaped), we can easily distinguish the two from a batch of Kenyan coffee.

To date, Front Street has tasted SL28 from multiple producing countries, such as versions from El Salvador and Costa Rica, and they all carry distinct blackberry acidity with similarly bright acidity. But compared with SL28 produced in Kenya itself, these beans often lack body. This brings us to Kenya's unique growing environment and processing methods—like the variety itself, they are indispensable parts of shaping Kenyan flavor.

Speaking of which, Front Street naturally had to brew a pot to taste it. The brewing subject this time is the Front Street Kenya · Cherry Tomato from Front Street's bean list. It comes from the Asali Processing Plant in the Thika region and is a single-origin bean produced from a blend of SL28 and SL34, using the classic Kenyan-style washed process.

Front Street Kenya · Cherry Tomato coffee beans

Region: Thika

Processing Plant: Asali Processing Plant

Altitude: 1550–1750 meters

Varieties: SL28, SL34

Processing Method: Washed

Flavor: Dark plum, cherry tomato, yellow sugar, black plum

When grinding this bean, you can already catch clear dark plum and cherry tomato acidity. After hot water is poured in, a yellow sugar-like sweetness gradually emerges. When tasted after brewing, the entry is quite full-bodied acidity, with the main flavors dominated by dark plum, cherry tomato, and plum, accompanied by obvious yellow sugar sweetness and a hint of oolong tea-like finish. The overall mouthfeel is round and full, making it comfortable and enjoyable to drink.

The above content is compiled by CoffeeHunters, a coffee news website.