From Unwanted Weed to Export Commodity: The Story of Knotweed
In rural Vietnam, knotweed (also known as wild amaranth or prickly amaranth) is a familiar sight. The plant grows wild everywhere, from rice paddy banks to roadsides and vacant lots. Young leaves are a favorite ingredient for many homemakers, who cook them into delicious and liver-cooling soups, stir-fries, or garlicky sautés—a perfect remedy for the oppressive tropical heat.
However, its rampant growth and prickly nature have earned it a reputation as a “pesky weed” among some. Farmers have often complained about its dense growth, which can smother their crops. But ironically, it’s this very same root that has now become a valuable “treasure.”
Knotweed Roots: A High-Value Commodity
Lately, people have been taking notice of knotweed roots, thanks to Chinese traders who are buying them at surprisingly high prices. According to Người Đưa Tin, in some parts of China, these roots fetch up to 40 Chinese yuan per kilogram, which is approximately 141,000 Vietnamese dong. The price goes even higher for dried roots.
In Vietnam, dried roots are currently being purchased by traders at prices ranging from 80,000 to 100,000 dong per kilogram, depending on quality and cleanliness. This is a significant difference compared to the price of fresh vegetables, which usually only costs a few dozen thousand dong per kilogram. Some astute farmers have started harvesting these roots instead of discarding them, thereby opening up a new avenue for economic development.

Why Are Knotweed Roots in High Demand?
According to research in traditional medicine and ancient medical texts, knotweed roots offer a plethora of benefits:
- They possess cooling, detoxifying, diuretic, blood-stimulating, and anti-inflammatory properties, making them ideal for treating abscesses, arthritis, and inflammation.
- Rich in vitamins and minerals, notably vitamins C and K, calcium, iron, and magnesium, they support joint health and boost immunity.
- Containing flavonoids and saponins, two potent antioxidants, knotweed roots help prevent aging and protect the liver.
“Knotweed roots can be used as a gentle herbal remedy,” shares PGS.TS Nguyen Thi Mai, a renowned herbal expert at the Vietnam Institute of Nutrition. “When combined appropriately with other herbs, they can positively contribute to treating various ailments.”
Not only is knotweed root valued in traditional medicine, but modern scientists are also intrigued by its potential as a natural ingredient for developing health supplements and treatments.
Farmers Reap Rewards from This Wild Plant
“My family has been growing knotweed for a long time, mostly for our own consumption and to sell the fresh leaves,” shares Nguyen Thi Ha from Dong Thap. “But recently, someone offered to buy the roots at double the price of the leaves. Now, I carefully dig up the roots, clean and sun-dry them, and sell them for almost 100,000 dong per kilogram. In contrast, I used to sell a whole basket of fresh leaves for just a few dozen thousand dong.”
Other farmers are also learning how to properly harvest, clean, and dry the roots, ensuring better quality and higher prices. This newfound appreciation for knotweed roots is not only boosting farmers’ incomes but also changing perceptions about this once-unwanted plant.

Important Considerations for Harvesting and Using Knotweed Roots
While knotweed roots present economic and health opportunities, there are some essential things to keep in mind:
- Avoid harvesting young roots: Young roots have fewer nutrients and are harder to dry properly. It’s best to harvest plants that are at least two months old.
- Clean thoroughly: Roots tend to be muddy, so wash them carefully and sun-dry them gently to preserve their beneficial compounds.
- Don’t overuse: While knotweed roots are natural remedies, they should not replace prescribed medications. Consult a healthcare professional before considering long-term use.
Conclusion: From Humble Roots to Abundant Opportunities
Who would have thought that the roots of a once-unwanted weed could become a valuable source of income for farmers? This transformation not only changes our perspective on wild plants but also reminds us that value can be found in the most unexpected places.
Instead of discarding what seems insignificant, let’s take a closer look at the simple things around us. You might just discover your own “gold mine” right in your backyard.