Growing and processing of Kona coffee
Kona coffee blooms in February and March. Small white flowers called Kona Snow cover the tree. Green berries appear in April. By late August, red fruit, called "cherry" due to resemblance to a cherry, start to ripen for picking. Each tree, hand-picked multiple times between August and January, offers around 20-30 pounds of cherry.
Pulper
Within 24 hours of picking, the cherry is run through a pulper, the beans are separated from the pulp, and then placed overnight in a fermentation tank. The fermentation time is about 12 hours at a low elevation or 24 at a higher elevation. The beans are rinsed and spread to dry on a hoshidana or drying rack. Traditional hoshidanas have a rolling roof to cover the beans in rain. It takes 7--14 days to dry beans to an optimal moisture level of between 10 and 13% (by Hawaii Department of Agriculture regulations: 9.5-12.5%). From here, the beans are stored as "pergamino" or parchment. The parchment is milled off the green bean before roasting or wholesale.
Peaberry
Kona coffee beans are classified according to seed. Type I beans consist of two beans per cherry, flat on one side, oval on the opposite side. Type II beans consist of one round bean per cherry, otherwise called a peaberry. Further grading of these two kinds of beans depends greatly size, moisture information, purity of bean type and size. The grades of Type I Kona coffee are Kona Extra Fancy, Kona Fancy, Kona Number 1, "Kona Select" ,and Kona Prime. The grades of Type II Kona coffee are Peaberry Number 1 and Peaberry Prime. There is also a lower grade of coffee called Number 3 which can not legally be labeled as "Kona".
Larva of root-knot nematode,
Coffea liberica
Coffea arabica
Infestations of the root-knot nematode damaged many trees in the Kona districts in the 1990s. Symptoms are single or clusters of trees with stunted growth, especially when transplanted. In 2001, rootstock from the Coffea liberica species was located to be resistant to the nematodes. It could be grafted with Coffea arabica 'Guatemala' variety to create a plant that naturally resists the pest, as well as produces a quality coffee product. The combination was named after Edward T. Fukunaga (1910--1984), who was superintendent of the University of Hawaii's Kona Research Station in Kainaliu in the 1950s through the 1970s.