On the Island of Maui a unique cultivar called Mokka is commercially cultivated. I first heard of it perhaps a decade ago and over the years I have heard things like it is a varietal brought from Yemen or Ethiopia; always an air of mystique around its origins. While it’s a wonderfully romantic notion that it is some unknown cultivar from who knows where, the reality is that there is nothing mysterious about it at all. The Mokka tree produces very small seeds that look more like split peas than coffee beans. Very tiny. The tree itself is very bushy compared to other cultivars with tiny cherries and narrow leaves. It is one of four cultivars planted on Maui. The Mokka planted there all originates from one tree at the CTAHR research station in Kainaliu on the big island of Hawaii, about 10 miles from the town of Kailua-Kona. It, like most of the cultivars at that research station, came from Brazil in the 1950’s or 60’s. When it was sent to Hawaii it was simply labeled Mokka. Mokka is a mutant of Bourbon that was documented long ago. It was well known by the time Uker’s book ‘All About Coffee’ was published in 1935 and written about by coffee researcher PJS Cramer earlier than that. It is a dwarf mutant, very bushy, looking more like a hedge than a coffee tree growing to only 4-6 feet tall, whereas Bourbon which it mutated from grows 20+ feet if left unpruned. Its appearance is very very close to that of the Laurina varietal discovered on the island of La Reunion in the 19th century. The distinguishing difference between the two is that Mokka has round beans. Laurina produces seeds that are sharply pointed on one end and often is referred to as ‘Bourbon pointu’ because of its shape. In fact both forms result from mutations of the same gene. Both are pleiotropic mutations (one gene causing several morphological changes, whereas most mutations cause only one small change, like the color of the cherry.)
The Bourbon mutant Mokka exists in the collections of many research stations around the world. But this varietal is low yielding and extremely difficult to harvest by hand so, to my knowledge, it hasn’t been commercially cultivated anywhere, at least on any scale. What is grown on Maui isn’t this mutant. It is something called ‘tall Mokka.’ At some point, intentionally or accidentally, the Mokka mutant hybridized with Typica, a tall variety genetically distinct from Bourbon. The resulting plant retains the small cherries, leaves and beans of the Mokka mutation but is a tall tree like Typica, but much bushier. It is this hybrid that is planted on Maui and nowhere else that I know of.
Interestingly both the Laurina and Mokka mutations produce seeds with half the caffeine of most other Arabica cultivars. Whether or not the Maui Mokka retains this characteristic I’m not certain, but it may be less than others.
Even with some of the mystery removed it is still quite an interesting varietal and I have become quite fond of it. In my experience, it seems to make a heavy bodied coffee that is very chocolaty and often with notes of dried fruit or spices. And as a natural processed coffee it can have a rose-like floral quality. Because of the small size of the cherry it seems ideal for the natural process, but unfortunately, except on farms that mechanically harvest like they do in Maui, it is quite unpractical to plant as it is very difficult and time-consuming to pick by hand.