Fish mint is a perennial herb native to Southeast Asia, known scientifically as Houttuynia cordata. It gets its common name from the strong, fishy smell released when its heart-shaped leaves are crushed. Widely used across China, Vietnam, Japan, Korea, and India, it serves double duty as both a culinary herb and a traditional medicine.
What Fish Mint Looks, Smells, and Tastes Like
Fish mint is a low-growing plant that spreads along the ground via underground stems called rhizomes, reaching six inches to about a foot and a half tall. Its leaves are blue-green, heart-shaped, one to three inches long, and sit on smooth, reddish-burgundy stems. When it flowers, it produces small cone-shaped spikes surrounded by four white petal-like bracts that can look almost like tiny dogwood blossoms.
The defining characteristic is the smell. Crushing a leaf releases a pungent, fishy odor that people tend to either love or find repulsive. The compound responsible is decanoyl acetaldehyde, a volatile molecule that breaks down over time into a slightly different compound with a more subtle, slightly waxy scent. This instability is part of why the flavor mellows considerably with cooking. Raw, the taste is assertive: fishy, herbal, and slightly sour, with a bite that some compare to cilantro in its polarizing effect on people.
How Fish Mint Is Used in Cooking
Both the leaves and the long, white, tangled roots of fish mint are edible, though different regions favor different parts. In Vietnamese cuisine, the leaves appear as a fresh herb alongside other greens in rice paper rolls, noodle soups, and salads. In parts of southern China, particularly Yunnan and Guizhou provinces, cooks prize the roots just as much as the leaves. The roots are washed, stripped of their fine brown root hairs, and used in several ways: stir-fried with chili and tomato, tossed raw into crunchy salads, or mixed into dishes like Dai-style lime chicken alongside other herbs.
The leaves work well in a simple Chinese-style salad dressed with garlic, sesame oil, soy sauce, and fresh chili. In northeastern India, particularly in Manipur and Meghalaya, the plant is a staple ingredient in chutneys and side dishes. Because the fishy flavor fades with heat, people who find the raw taste too intense often prefer it cooked.
Traditional and Researched Health Properties
Fish mint has a long medicinal history in China, where the leaves and stems have been used to treat colds, coughs, fevers, and pneumonia. Modern research has started to investigate the compounds behind these traditional uses, focusing primarily on the plant’s essential oils and flavonoids.
Lab studies have identified anti-inflammatory, antibacterial, and antiviral activity. One of the plant’s key compounds, sodium houttuyfonate, significantly reduced levels of inflammatory signaling molecules in cell studies. Extracts from the plant also inhibited histamine release in a dose-dependent manner, which is relevant to allergic reactions. On the immune side, fish mint extracts increased the activity of certain immune cells (CD4+ and CD8+ T cells) and boosted the release of signaling molecules that help coordinate immune responses.
Antiviral research has shown that fish mint compounds can interfere with viral replication machinery. One flavonoid found in the plant suppressed replication of a common diarrhea-causing virus by 50 percent at very low concentrations. Researchers have also noted inhibition of enzymes used by SARS-related coronaviruses, though this work remains at the laboratory stage rather than representing a proven treatment.
The major bioactive compounds in fish mint, particularly quercetin and related flavonoids, are the same antioxidants found in many fruits and vegetables. These contribute to the plant’s broad antioxidant profile, though eating fish mint as part of a varied diet is more realistic than expecting it to function as medicine on its own.
Safety Considerations
Eating fish mint as a food, whether raw or cooked, carries very little risk. A review of adverse reaction reports found that problems were overwhelmingly linked to processed pharmaceutical preparations, particularly injectable forms used in Chinese hospitals, not to eating the plant itself. Oral consumption in the form of teas or as a food ingredient rarely caused anything more serious than mild digestive symptoms like abdominal discomfort or diarrhea in a small number of people. No cases of kidney disease or cancer were linked to eating the plant.
Some people do experience mild skin reactions such as rashes or hives, so if you notice any allergic-type symptoms the first time you try it, that is worth paying attention to.
Growing Fish Mint (Carefully)
Fish mint thrives in moist to wet soil in sun or shade, and will even grow submerged in a few inches of water. It is extremely easy to grow, which is precisely the problem. The plant spreads aggressively through underground rhizomes and has earned a reputation as one of the most invasive groundcovers a gardener can introduce. One horticulturist compared it to mint in “the way in which they invade, defying eradication and reveling in their obnoxious behavior.”
If you want to grow it, the only recommended approach is to keep it in a strong container from which the rhizomes cannot escape. A buried pot, a raised bed with solid walls, or a large planter on a patio all work. Drier soil can slow its spread somewhat, but in the moist conditions the plant actually prefers, it will colonize an area rapidly. In gardens where it has been planted directly in the ground, removing it can take years of persistent effort.
An ornamental variety sometimes sold as “chameleon plant” has multicolored leaves splashed with red, pink, and cream. It is the same species with the same invasive tendencies, just dressed up. The variegated form still carries the characteristic fishy smell.
Other Names for Fish Mint
You may encounter this plant under a variety of names depending on where you are. In English, it goes by fish mint, fish herb, fish leaf, chameleon plant, and rainbow plant. In Vietnamese it is called diếp cá, in Japanese dokudami, in Chinese yú xīng cǎo (meaning “fishy-smelling herb”), and in several northeastern Indian languages it is known by local names that roughly translate to “fish-scented leaf.” If you see Houttuynia cordata on a plant label or seed packet, it is the same thing.