This is a coffee Variety that is commonly seen within Kenya,
The SL28 is one of the three special varieties that was designed by the Scott Agricultural Lab ( hence the naming SL). These were developed to prevent drought resistance.
This is a Tall plant that is from the Bourbon Lineage, these have a lower Yeald than intended and produce better in a higher altitude environment compared to the SL28. It's not at drought and disease resistance as expected but it did achieve a high sensory quality, which explains its ongoing popularity.
The SL34 is a little bit more hearty but not too much. it has s different leaf colour to the SL28 worked better at a lower altitude and still produces a quality cup. They are a bit more productive which could lead it to be more part of the Typica group but it gets a little detailed with the science. The SL14 is also found throughout Uganda as well.
World Coffee Research indicates that genetic testing of both SL14 and SL34 suggests they are closer to Typica than Bourbon, meaning the French Mission selection story might be incorrect.
Most of the information can be found at the World Coffee Research at https://worldcoffeeresearch.org/
but what we really like is that these produce awesome coffees and with learning more about each variety we appreciate it a bit more.