What is SL28 coffee?

The story of SL28 is inextricably linked to the history of Kenyan coffee. In the 1930s, Scott Agricultural Laboratories (SL) began a program to identify and breed coffee varieties that could thrive in the unique climate of Kenya. The goal was to find plants that were not only productive but also capable of producing the high-quality, acidic, and complex cup that the region was becoming famous for. SL28 was the standout result of this research.

What makes SL28 so special is its sensory profile. It is the definition of 'bright' coffee. When you drink a high-quality SL28, you are often met with a vibrant, wine-like acidity, notes of blackcurrant, tomato, and citrus, and a lingering, syrupy sweetness. This profile is so distinct that it has become the benchmark for what many people consider to be the quintessential Kenyan coffee experience. It is a variety that truly shines when processed using the traditional washed method.

Despite its fame, SL28 is not the easiest plant to grow. It is susceptible to coffee leaf rust and coffee berry disease, which has led to the development of newer, more resistant varieties like Ruiru 11 and Batian. However, many farmers and roasters continue to prioritize SL28 because, quite simply, the flavor is unmatched. It is a variety that requires a specific environment—high altitude, rich volcanic soil, and careful management—to reach its full potential.

In practice, SL28 is a favorite among specialty roasters who want to showcase the potential of African coffee. It is a variety that rewards the drinker who enjoys a complex, lively cup. If you are looking for a coffee that challenges your palate and offers a vibrant, fruit-forward experience, look for bags that specifically mention SL28. It is a testament to the success of early 20th-century agricultural research and the enduring quality of Kenyan coffee.