The Rainy Season’s Delicacy: A Wild ‘Water-Loving’ Treat That’s Worth the Hype

The Floating Water Coconut Vegetable of the Mekong Delta: A Seasonal Delicacy

The annual flood season in the Mekong Delta, from July to November, brings not only a bounty of produce but also a proliferation of wild vegetation, giving rise to unique and delectable specialties. Among these, the water coconut vegetable, or Jussiaea repens oenotheracene, stands out for its intriguing characteristics.

Also known as du long thai, thuy long, rau dua trau, and rau muong bo, this versatile plant can thrive in both arid lands and flooded areas.

In terms of form, the water coconut vegetable is a herbaceous plant with numerous slender branches. Its stem is cylindrical, soft, and segmented. The leaves are long and oval-shaped, growing alternately with a rounded base and glossy surfaces.

In Vietnam, this vegetable is found in all three regions, but it flourishes most prominently in the Mekong Delta. Locals share that it typically grows in flooded areas such as ponds, lakes, and rice fields. Notably, the plant possesses small floats along its stem, enabling it to stay buoyant on the water surface. During the rainy season, the water coconut vegetable experiences rapid and robust growth.

Historically, water coconut plants used to grow densely and were considered weeds by farmers, often uprooted or fed to livestock as they competed with rice crops. Only a select few were harvested by locals for simple meals, serving as a source of nourishment during challenging times.

Recently, the water coconut vegetable has gained popularity as a sought-after specialty in cities. It can be prepared in a variety of ways, including boiling, stir-frying, or dipping in hot pot. Ms. Thanh from An Giang shares that dipping the vegetable in fermented fish sauce enhances its crispness and blends perfectly with the sauce’s robust flavor, making it addictive to many. While it may have a slightly pungent taste and a ticklish sensation on the first try, this vegetable offers a delightful and refreshing experience once you acquire its taste.

Ms. Thanh also mentions that locals can distinguish between two types of water coconut vegetables: the “rice” variety and the “buffalo” variety. Although both are edible, the “rice” type is generally preferred for its milder flavor, while the “buffalo” variety has a slightly bitter taste.

During the flood season, Mekong Delta residents actively harvest water coconut vegetables for sale. With its potential for generating income, many families have started expanding their cultivation of this vegetable.

According to surveys, water coconut vegetables are relatively inexpensive in local markets, but their price can soar up to 80,000 VND per kilogram on e-commerce platforms and specialty vegetable stores. Despite the higher price compared to common vegetables, it remains in high demand due to its exceptional taste and safety profile, free from chemical residues.

In restaurants and eateries across the Mekong Delta, the water coconut vegetable is transformed into a myriad of delicious dishes, including raw salads, boiled vegetables with fermented fish sauce, herb salads, hot pots, stir-fries, and additions to iconic dishes like bún riêu (vermicelli soup with crab) and bún mắm (vermicelli with fermented fish sauce).

Beyond its culinary appeal, the water coconut vegetable offers health benefits as well. In traditional medicine, it is believed to have a sweet and淡 flavor, a cooling nature, and is used for heat dissipation, detoxification, diuresis, and reducing edema.