Preserving wild jambolan tree

The wild jambolan tree (Syzygium cumini (L.) Skeels) is a native timber species naturally distributed from Da Nang southward through the South Central Coast and the western Mekong Delta. Because of its high timber value and traditional fruit harvesting, wild populations have declined sharply, threatening this valuable genetic resource.

Drawing on real-world observation, the author began researching conservation and forest-economy development around the wild jambolan tree in 2020, funded entirely from personal resources. This work represents Viet Nam's first scientific effort to conserve the species' genetic resources through controlled clonal propagation, combined with developing a production process for Phulas wine made from 100 percent wild jambolan fruit.

Declining genetic resources and the urgent need for conservation

The wild jambolan tree, of the Myrtaceae family, is a large native evergreen naturally distributed from Da Nang through the South Central Coast provinces (Quang Nam, Quang Ngai, Binh Dinh, Phu Yen, Khanh Hoa, Ninh Thuan, and the former Binh Thuan) and extending into the south (Dong Nai, An Giang, and transitional areas).

The tree thrives in sunlight, has deep roots and thick bark, tolerates both drought and waterlogging, and adapts well to basalt soil, nutrient-poor hilly terrain, and agroforestry transition zones. It typically grows 10 to 30 meters tall, with a trunk diameter of up to 50 centimeters and a lifespan exceeding 100 years. It flowers from March to May, with fruit ripening to a deep purple-black from July to September, carrying substantial nutritional and medicinal value from its rich anthocyanin, phenolic, and triterpenoid content.

The wild jambolan tree suits a tropical-to-subtropical climate with average temperatures of 20-30°C, annual rainfall of 1,000-2,000 mm, and soil pH of 5.5-7.5. Its drought and waterlogging tolerance exceeds that of many other species, its deep roots help prevent erosion, and its broad canopy improves local microclimate. Conservation therefore sustains not just genetic resources but broader ecological functions: carbon absorption, watershed protection, and forest enrichment.

The fruit's biochemical profile includes roughly 25 percent inedible waste, with the edible portion containing 80.8 percent water, rich anthocyanins (150-200 mg/100g), quercetin, gallic acid, ellagic acid, and oleanolic acid, along with protein, natural sugars, and organic acids, plus measurable calcium, phosphorus, iron, and vitamins in the fresh fruit. The seeds also contain 6.3-8.5 percent protein and notable crude fiber.

The author surveyed ecological zones from Da Nang through the central and western Mekong Delta regions, testing multiple clonal propagation and cultivation methods to build a scientific basis for both production guidance and wine research. The work has received copyright protection through three certifications from Viet Nam's Copyright Office, covering the conservation and clonal propagation research, the Phulas wine production process, and the cultivation procedure.

Given the hardship facing farmers in the former Phu Yen province, the author donated the clonal propagation method to the locality, which assigned implementation to Tay Hoa district and the Dong Xuan Protection Forest Management Board (now part of Dak Lak province). While Tay Hoa's rollout faced setbacks, the Dong Xuan board successfully applied the propagation method via air-layering, planting 5 hectares in 2025 with 12 hectares planned for 2026.

The Dak Lak Provincial People's Committee has since incorporated the tree into forest planting programs, and the provincial Forest Protection Sub-Department officially recognized the Dong Xuan board's jambolan stock as a certified forestry seed source for preserving elite mother trees, marking the first time in Vietnamese forestry history the species has been used for afforestation and forest enrichment.

A distinctive Vietnamese wine

To sustain both conservation and raw-material development, the author refined a nine-step production process for Phulas wine made entirely from wild jambolan fruit, ensuring fully natural ingredients.

On February 1, 2025, a seven-member quality assessment panel chaired by Dr. Nguyen Trong Tung, Director of the Phu Yen Department of Agriculture and Rural Development, concluded that Phulas Wine carries a deep red color, moderate tannin, and a fermented aroma resembling grape wine, making it well suited for entertaining honored guests. Feedback from thousands of tasters both domestically and internationally has praised its bright purple hue, smooth texture, distinctive aroma, and approachable tannin.

On May 1, 2026, Jose, Chairman of the World Wine Club in Da Nang and Honorary Vice Ambassador of the Spanish Embassy in Viet Nam, described Phulas wine as a genuinely distinctive Vietnamese specialty on the global wine market, noting its bright purple color, characteristic aroma, and balanced tannin.

This conservation and clonal propagation effort, paired with Phulas wine development, stands as pioneering scientific work in Viet Nam. Its results in Dak Lak affirm strong feasibility, supporting biodiversity conservation, climate adaptation, and Viet Nam's Net Zero 2050 goal, a model of the circular bioeconomy that preserves valuable native genetic resources while elevating Vietnamese agricultural products on the global scientific and commercial stage.