SL34 (Kenya variety)

Kenyan variety selected by Scott Laboratories, of French Bourbon origin. Profile: phosphoric acidity, redcurrant notes, dark chocolate. Better adapted to lower altitudes than SL28. Often blended with SL28.

Background & Context

SL34 is the companion variety to SL28 in Kenya's specialty coffee heritage — selected by Scott Agricultural Laboratories in 1935 from French Mission Bourbon lineage, making it a Bourbon descendant rather than sharing SL28's drought-resistant Tanganyika lineage. SL34 produces a slightly different cup profile than SL28: while SL28 is characterised by intense blackcurrant and cassis, SL34 tends toward more tropical fruit (mango, papaya), moderate citrus acidity, heavy body, and a sometimes syrupy mouthfeel. SL34 is also more resistant to drought than SL28, giving it agronomic advantages on lower-altitude or drier Kenyan farms. Many Kenyan cooperative lots are blends of SL28 and SL34 cherries — the proportion varies by cooperative and altitude zone, producing the flavour diversity characteristic of Kenyan coffee. SL34's Bourbon ancestry means it shares the variety's characteristic sweetness and balanced acidity — traits that make it more accessible to consumers unfamiliar with SL28's assertive blackcurrant intensity. This is why many Kenyan cooperative lots offered at competitive price points (Kenya AB, not AA) are SL34-dominant: the variety's lower altitude adaptability makes it available from a wider range of farms, including mid-altitude producers who cannot achieve the extreme acidity and complexity of high-altitude SL28 production. World Coffee Research's variety characterisation confirms SL34 as a genetically distinct cultivar from SL28, with different disease susceptibility profiles and agronomic characteristics.

Practical Use

For roasters who want to understand why two Kenyan coffees from the same county taste different, SL28/SL34 variety composition is often the explanation. A Nyeri AA that is predominantly SL28 will show the intense cassis character associated with Kenyan specialty; the same county's SL34-dominant lots will be more tropical and full-bodied, better suited to milk-based drinks or espresso blending. Cooperative-level sourcing documentation that specifies variety composition allows roasters to predict cup profile with confidence. In the specialty trade, pure SL28 commands a modest premium over SL34 or mixed lots — the variety's intensity is harder to replicate and more immediately distinctive in blind tasting competitions.

Related Terms

Related terms: SL28/SL34, SL28, Kenya coffee, Bourbon (French Mission), Body.