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Editorial sacred-geometry artwork for SL20; not a documentary photograph
Variety

SL20

Quick definition

SL20 is a coffee variety selected by Scott Agricultural Laboratories in Kenya. It is part of the famous 'SL' series, known for its high quality and adaptation to the Kenyan highlands.

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What is SL20? It is one of the many varieties selected by Scott Agricultural Laboratories (SL) in Kenya during the 1930s. The SL series is legendary in the specialty coffee world, having been developed to identify high-quality, high-yielding trees that could thrive in the unique climate and soil conditions of the Kenyan highlands. SL20, like its more famous siblings SL28 and SL34, was chosen for its specific performance characteristics.

Coffee SL20 is part of a rigorous selection process that took place over several years. The researchers at Scott Agricultural Laboratories evaluated hundreds of individual trees, looking for those that demonstrated superior cup quality, drought tolerance, and resistance to local pests. While SL28 and SL34 became the most widely planted, other selections like SL20 were also part of the broader effort to improve the quality and productivity of Kenyan coffee.

In the cup, SL20 is often characterized by the classic Kenyan profile: bright, vibrant acidity, complex fruit notes, and a clean finish. However, because it is a distinct selection, it may have subtle differences in flavor profile compared to the more common SL varieties. It is highly sought after by roasters who specialize in Kenyan coffees and appreciate the nuance that different selections can bring to a single-origin offering.

For the coffee professional, SL20 represents the history of coffee research in East Africa. It is a reminder of the importance of local selection and the impact that dedicated agricultural research can have on the quality of the final product. When you encounter an SL20, you are tasting the result of decades of careful observation and selection, aimed at capturing the best of the Kenyan terroir.

In practice, SL20 is a prized variety that highlights the diversity within the Kenyan coffee landscape. It is typically grown at high altitudes, which contributes to its dense bean structure and complex flavor development. For the consumer, it offers a unique opportunity to explore the depth of Kenyan coffee beyond the most common varieties, providing a bright and memorable experience in the cup.