SL28

SL28 is perhaps the most famous coffee variety to emerge from East Africa. Developed in the 1930s by Scott Agricultural Laboratories (SL) in Kenya, this cultivar was specifically bred to thrive in the unique climate of the Kenyan highlands. It is a selection from a drought-resistant variety originally found in Tanganyika, and it has since become the gold standard for the Kenyan coffee industry, defining the bright, vibrant, and fruit-forward profile that the region is famous for.

When asking what is SL28, you are looking at a variety that is synonymous with high-quality specialty coffee. The plant is known for its distinct, broad leaves and its ability to produce a cup with remarkable intensity. The hallmark of SL28 is its complex, wine-like acidity, often described as having notes of blackcurrant, tomato, or citrus. This intense flavor profile is a result of both the genetic makeup of the plant and the specific terroir of the high-altitude volcanic soils where it is typically grown.

Despite its incredible cup quality, SL28 is not without its challenges. It is highly susceptible to coffee leaf rust and coffee berry disease, which makes it a high-risk, high-reward variety for farmers. Because of these vulnerabilities, it is often grown in smallholder plots where farmers can provide the intensive management required to keep the trees healthy. The dedication required to cultivate SL28 is a testament to its value; it remains one of the most sought-after varieties by roasters worldwide.

In practice, SL28 is a variety that demands respect during the roasting process. Its high acidity and delicate aromatics can be easily muted by over-roasting, so it is typically roasted to a light or medium level to preserve its vibrant character. For the consumer, an SL28 coffee is an experience in intensity and complexity. It is a perfect choice for those who enjoy a bright, clean, and highly aromatic cup that showcases the unique potential of East African coffee.