Development of Pitanga (Eugenia uniflora L.) as a Commercial Crop for Hawai'i

Eugenia uniflora L., (pitanga, Surinam cherry, pitangueira) is native to Brazil and other countries in northern South America. In its native range, this fast-growing shrub or small tree usually produces two crops per year of relatively small (2.5 to 3.5 cm), juicy fruits. The fruits ripen quickly, taking only about six weeks to reach maturity from anthesis. Differing from bush to bush, the mature fruits range in color from orange to red to dark purple. The juicy sweet-acid pulp encloses one or occasionally more seeds. The fruits, especially the dark purple ones, are an excellent source of antioxidants such as cyanidin-3-glucoside, delphinidin-3-glucoside, the xanthophyll lutein and the carotenoid lycopene. The ripe fruits can be eaten fresh or they can be processed into frozen pulp, juices, jams, jellies and other food items. Plants prosper in soils with abundant organic matter and a pH of 5.5-6.5 although they can grow acceptably in many different situations. The seedlings establish quickly and produce more heavily and earlier when grown in full sun. They are easy to grow without fertilization although they respond very positively to fertilizer and water applications. Plants come into bearing from seed in three to four years, although superior grafted plants can produce fruits when the grafts are one to two years old. A large trial planting of pitanga is in its third year in the ground at the University of Hawai'i Kona Experiment Station. Fertilizer trials allow us to provide organic and non-organic fertilizer recommendations for small-scale producers. We also collect information on fruit yield and fruit size of individual plants. Flowering on any bush is asynchronous, with open flowers and ripe fruits often present at the same time; this does present some harvest challenges. In the Kona planting, flowering between individual bushes is also not well synchronized and this leads to the possibility of significant year-round production of the crop within one field. Additional laboratory analysis on acid, brix, and other chemical and nutritional contents of mature fruits allow for further selection and development of superior clones for Hawai'i. Post-harvest refrigeration evaluations are also being conducted. Successful grafting trials using the improved dark purple cultivar ‘Zill Dark' yielded good results with veneer grafts and a row of ‘Zill Dark' has been added to the experimental planting for comparison and as a source of budwood. Grafted superior local selections from this field will be provided to cooperating growers.