Edible & Medicinal Uses of Japanese Knotweed (Polygonum Cuspidatum)
Japanese Knotweed in flower attracts numerous pollinators.
Medicinal Applications
Lyme Disease
May in Vermont is the perfect time to harvest Japanese Knotweed roots for making valuable medicine. This invasive plant , a relative of buckwheat, is often spread by road maintenance and farm machinery. If you are going to harvest this plant for food or medicine, it’s important to obtain it from wild settings free from road salt, exhaust, and chemical fertilizers and herbicides. There is no chance of over-harvesting this rapid-spreader. So, digging the roots for medicine is something of a community service.
From my brief layperson’s perspective, I’ve come to know Japanese knotweed as an amplifier that potentiates other medications, helping both antibiotics and other lyme-treatment herbs perfuse muscles and synovial fluid. This is why I personally take it alongside anything else, having suffered for over a decade with central nervous system Lyme. —MH
Stephen Buhner is a master plant/ herbal practitioner and medical researcher and has authored definitive books on the herbal treatment of Lyme disease and its co-infections. Naturopathic doctors use his work as a foundation for the treatment of their patients.
This is what Stephen writes about Japanese Knotweed in his book Healing Lyme:
“Polygonum cuspidatum’s constituents cross the blood-brain barrier where they exert actions on the central nervous system: anti-microbial, anti-inflammatory, as protectants against oxidative and microbial damage, and as calming agents. The herb specifically protects the brain from inflammatory damage, microbial endotoxins, and bacterial infections.
“Knotweed enhances blood flow especially to the eyes, heart, skin, and joints. This makes it especially useful in Lyme as it facilitates blood flow to the areas that are difficult to reach to kill the spirochetes. It is a drug and herb synergist, facilitating the movement of other herbs and drugs into these hard-to-reach places when taken with them.
“Thus, the herb has a number of specific actions in the treatment of Lyme disease: (1) stimulating microcirculation, especially to the eye, knees heart, brain and skin, which helps carry active constituents to those locations to affect spirochete presence; (2) reducing inflammation in tissues, thus lessening both skin and arthritic impacts from the spirochetes; (3) protecting and correcting heart function and reducing inflammation in heart tissue, especially helping with symptoms associated with Lyme carditis: lightheadedness, shortness of breath palpitations, and chest pain; (4) reducing autoimmune reactions to Lyme; (5) promoting wide-spectrum antibiotic/antiviral action, including (mildly) against spirochetes; (6) enhancing healthy immune function; (7) acting as a synergist with other herbs or drugs in the treatment of Lyme; (8) protecting endothelial integrity from Lyme spriochetes and Lyme coinfections agents such as Bartonella; (9) acting as a fairly gentle anti-biofilm agent; and, (10) most importantly, reducing inflammation in the brain and central nervous system, helping restore function during neuroborreliosis.”
Healing Lyme, Second Edition by Stephen Harrod Buhner, Raven Press, Silver City, NM 2015
You can dig the roots either in the spring or the fall. If you wish to make your own tincture or medicine, there are several ways to do this. You can clean and slice the roots and dry them for use in making tinctures or teas—or you can simply grind the dried roots and consume the powder directly.
2. SARS-Related Viruses (Covid 19 is a SARS-related Virus)
This is what Stephen Buhner writes in his book Herbal Antivirals:
“Upon infection by the SARS virus, similarly to influenza, inflammatory cytokines are strongly upregulated. IFN-γ, CXCL10, IL-1ß, TNF-α, and IL-6 are primary, IL-6 particularly so. RANTES, MCP-1, and IL-8 are elevated in about half of those who are infected. The p38 MAPK pathway is highly stimulated and as the infection progresses levels of PGE2 (prostaglandin E2) and TGF-ß both rise (with a later elevation of IL-2). Lowering TGF levels is very helpful (Angelica sinensis, Astragalus mongholicus). HMGB1 levels during SARS cytokine cascades are high, especially in those who die. During the infection, the cytokine cascade initiates a massive immune cell migration, infiltration, and accumulation into lung tissues. The older the infected animal (human or otherwise), the greater the cytokine upregulation and the worse the outcome. Sharply reducing IL-1ß has been found to significantly decrease the impact of the disease on the infected and to inhibit mortality (Japanese knotweed — i.e., Polygonum cuspidatum — Chinese senega root, Chinese skullcap, cordyceps, kudzu, and boneset).
Severe hypoxia occurs in the cells that are affected (and in the person so afflicted). The RAS-stimulated cellular hypoxia generates high levels of free radicals through the rapid increase of angiotensin II, i.e., a hypoxia-reoxygenation injury cycle. In essence an abundance of hydrogen peroxide and superoxide radicals is generated. The high levels of angiotensin II stimulate free radical formation from endothelial cells, vascular smooth muscle cells, and mesangial cells as well. In short the excessive angiotensin II levels (due to the destruction of ACE-2 cells by the virus) cause massive damage to the lung, lymph, and spleen tissue. Protecting the cells from the induced hypoxia significantly reduces the damage in the lungs. (Rhodiola is specific for this. It prevents hypoxia-induced oxidative damage, increases intracellular oxygen diffusion, and increases the efficiency of oxygen utilization.)
The virus specifically targets (and replicates within) ciliated cells, destroying the cells and their capacity to move mucus up and out of the lungs. (Cilia-protective herbs are cordyceps, olive oil and leaf, the berberine plants, and Bidens pilosa.) Autoantibodies are produced that begin to attack host epithelial and endothelial cells, increasing the destruction. Reducing the autoimmune response (rhodiola, astragalus, cordyceps) and protecting endothelial cells (Japanese knotweed) is crucial. “
Buhner, Stephen Harrod. Herbal Antivirals: Natural Remedies for Emerging & Resistant Viral Infections . Storey Publishing, LLC.
One can begin to appreciate the power of this plant.
Culinary Applications
The young shoots of Japanese Knotweed are crisp and tangy, and particularly delicious when simply flash sauteed and then glazed with something slightly sweet and salty to balance their tanginess. I think that maple-mustard-garlic sauce is ideal for this purpose. Heat a small amount of oil in a pan and sprinkle in some coarse salt, then toss in the Japanese knotweed shoots—the shoots are tender anywhere from 4-12”…do a test to sample if the stalks are fibrous or not. Toss the shoots in hot oil until they wilt and until one side slightly browns or crisps, then either turn down the heat or remove them to a bowl and toss in a dressing of mustard, maple, garlic and perhaps a little soy sauce. If you like, you can put a small amount of sake in the pan before removing them, to coat everything. You can also dress them any way you like…adding miso, red pepper flakes, toasted sesame oil, sesame seeds, sake…I Iike to offset their natural tang with hot-sweet-savory flavors. This kind of dish can be served either hot or cold.
The stems and leaves can also be juiced and used like rhubarb juice. Some people make wine and jam from Japanese knotweed. I juiced some once and made a probiotic water kefir from it, and it worked well as a mild, herbal drink. Given its sourness, many such recipes use large amounts of sugar, which I personally don’t wish to promote. Tanginess is a flavor we should celebrate on its own merits, without having to mask it with copious amounts of refined sugar, in my opinion!
Japanese knotweed shoots are rich in vitamin A, resveratrol, zinc, manganese, potassium, and vitamin C . Most supplements called ‘resveratrol’ (a powerful antioxidant) are now made with Japanese knotweed.
Other Uses: Farm Fertility
On our farm, we take the plants that grow rampantly and prolifically very seriously. Every plant concentrates a certain nutrient profile in itself, and as we attempt to learn how to build native fertility from plants and materials available on site, Japanese knotweed is one we have used to make botanical extracts. Since Japanese knotweed reproduces prolifically from the smallest cuttings, it’s important to use this plant carefully to prevent its spread. We pull the stalks whenever we see them, then pack the plant material in a garbage can, and fill the can with water. We allow this mix to brew in the sun for many months to over a year, and then add the concentrated liquid to water or to compost where the anaerobic material becomes aerobic before application. As mentioned above this plant concentrates potassium, zinc, and manganese—and the process of fermentation can make the nutrient bioavailable to the soil and other plants without risk of spreading the knotweed.
Useful Links
INVASIVE KNOTWEED SPECIES AS A RICH SOURCE OF ANTIOXIDANTS https://www.cabi.org/ISC/FullTextPDF/2018/20183332869.pdf
JAPANESE KNOTWEED:DREADIBLE EDIBLE http://www.eattheweeds.com/japanese-knotweed-dreadable-edible/
JAPANESE KNOTWEED AND THE CULINARY CONTROL OF INVASIVES https://northernwoodlands.org/knots_and_bolts/japanese-knotweed-culinary-control-invasives
PROFILE OF BIOACTIVE COMPOUNDS IN THE MORPHOLOGICAL PARTS OF WILD FALLOPIA JAPANICA (HOUT) AND FALLOPIA SACHALINENSIS (F. SCHMIDT) AND THEIR ANTIOXIDATIVE ACTIVITY https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6479739/
For those who wish to make their own medicine, you can find good instructions here: https://blog.mountainroseherbs.com/guide-tinctures-extracts
We sell a high quality wild-farm-harvested tincture here in our farm shop for those who don’t wish to make their own.