If you've ever tasted a Kenyan coffee that left you speechless, it's very likely that it had something to do with these two letters: SL.
SL28 and SL34 are two coffee varieties developed in the 1930s at the Scotts Agricultural Laboratories, an agricultural research and experimentation station in Kenya. Their creation was no accident: the goal was to find plants more resistant to disease and better adapted to the conditions of the Kenyan highlands, without compromising—rather, enhancing—cup quality. A difficult balance to achieve… but one that was more than successfully accomplished here.
SL28: fruit intensity and character
In tastings, the SL28 variety typically stands out for its bright acidity (sometimes citrusy, other times more like currant), a silky texture, and a clarity of flavor that makes it unmistakable. Its fruity profile can range from mango and orange to red fruits, and it is often a favorite among those seeking expressive coffees with character.
Although its drought resistance is remarkable —one of the reasons it was selected—, it remains vulnerable to pests and diseases such as coffee rust, making its cultivation a job that requires experience, dedication and great care.
SL34: Deep sweetness and balance
The SL34 variety, on the other hand, offers a somewhat rounder and more comforting profile: fuller body, caramel sweetness, and a less sharp, though equally vibrant, acidity, with notes of tropical fruits, currants, and black tea. It's the variety that provides balance and texture, ideal for those who enjoy a rich, complex, and structured cup.
Although its development also aimed to improve productivity and resilience, in practice SL34 requires very specific conditions to reach its full potential: nutrient-rich volcanic soils, high altitudes, and regular rainfall. Therefore, it's not a variety you can find just anywhere in the world, and its presence remains strongly linked to East Africa.
A legacy that transcends Kenya
SL28 and SL34 not only redefined Kenyan coffee: they laid the foundation for a new way of thinking about the quality and value of African coffee. They helped position Kenya as one of the most highly regarded regions in the world of specialty coffee, and they remain a benchmark for tasters, roasters, and coffee lovers worldwide.
They have also influenced other producing countries which, inspired by their profiles and history, have tried to cultivate them in different contexts, albeit with mixed results. Because yes, they are demanding varieties, and only under very specific conditions can they express their full potential.
Our menu regularly features the work of our partner producers in South America who have achieved great results with these varieties, such as Darwin Moreno and his SL28 in Honduras, or the Esperanza SL34 Natural Mystic in Nicaragua. These are two examples of how, with dedication and the right environment, these coffees can shine far beyond Kenya.
What it means to us
At Right Side, working with a batch of SL28 or SL34 isn't an everyday occurrence. We know that behind each one lies meticulous work at the source, dedicated cultivation, and a clear intention to offer the very best. That's why, when they arrive on our menu, they do so with our full attention focused on respecting and highlighting what they already bring from the field.
If you enjoy juicy coffees with defined acidity, fruity notes, and a complexity that evolves with every sip, this is a family worth exploring. SL28 and SL34 are more than just varieties: they are part of the history of modern coffee and an invitation to discover what happens when science, agriculture, and a passion for flavor come together.