That is the introduction nearly 100% of us have to Wasabi (Wasabia japonica), sometimes called Japanese Horseradish. Unfortunately, we probably haven’t had real Wasabi at all. That green paste we were served is usually horseradish mixed with vinegar, food coloring and mustard. Most restaurants and sushi bars serve imitation Wasabi. Even the ‘Wasabi Paste’ found in specialty shops is usually imitation Wasabi. The majority of Japanese are generally unaware they are often served imitation Wasabi in their restaurants and sushi bars.
That's because authentic Wasabi is very expensive and scarce; demand far exceeds supply. Additionally, fresh Wasabi begins lose flavor almost immediately when grated and exposed to air, so it doesn't keep freshly prepared for long. Fresh Wasabi has the same immediately hot intensity of imitation Wasabi but it’s quickly replaced by a complex flavor, leaving you wanting more.
Fresh Wasabi is very sought after, and is served primarily in a few high-end sushi bars and restaurants here and abroad. If you are lucky enough to be in such an establishment, a freshly peeled wasabi root will be brought to your table and grated, much like fresh Parmesan although many times more costly. Fresh Wasabi root is also dried and ground into a powder which, when mixed with water just before use, creates a Wasabi paste not unlike imitation Wasabi in appearance. However, real Wasabi is milder and sweeter.
Fresh Wasabi roots sell for up to $100 per pound; one pound contains just a few roots. Restaurants will also buy fresh Wasabi stems and leaves, used in salad dressings or pickled in sake. Do the math. If you can create the right growing conditions, Wasabi could be a great market crop.
Wasabi is exacting about its growing conditions and thus not as widely grown. Cold mountain streams are ideal as they meander at the edge of the forest canopy. In Japan, wild Wasabi grows on the shaded wet stream banks in cool climates. It is not sun-tolerant and prefers cool summers with high humidity. Here's a short video of wasabi growing in a Japanese mountain stream.
Chris Jones, Frogfarm Wasabi, Holds Wasabi Plant
Wasabi Growing in Flooded Gravel Beds
Much experimentation of alternate growing techniques is being carried out in the U.S. and Canada. Some success is reported in Oregon, Washington State and the North Carolina mountains. In fact, Clemson University has joined forces with North Carolina State University – both are agriculture schools – to establish the first wasabi research project in the United States. Wasabi stands a good chance of being a tobacco-replacement crop, Clemson officials say. Doug Lambert, owner and founder of Real Wasabi, LLC has a 75 acre farm in Collowhee, NC where they have promising field tests of growing Wasabi in the mountain streambeds. I understand they also have a location in nearby Cashiers, NC.
Pacific Coast Wasabi has perfected the techniques for growing semi-aquatic Wasabi in a controlled greenhouse environment and is now expanding into a commercial facility. Agriculture Canada has also identified Wasabi as a potential new agricultural crop for British Columbia.
Wasabi, a member of the same family as cabbage and mustard, can be grown in soil under shade cloth; however, dirt-grown Wasabi doesn’t fetch as high a price as semi-aquatic Wasabi. More frequently, Wasabi growers are diverting cold mountain streams through shallow gravel beds planted with Wasabi. The Wasabi rhizome can take 2-3 years to mature to a length of half a foot or more and a 1 inch diameter. When harvested, side roots are pulled off and used to start new plants, which may grow to 2 feet high and wide.
Wasabi has antibacterial qualities, and some holistic health practitioners claim it strengthens the immune system, reduces mucus, and detoxifies the liver. It has been suggested that Wasabi can help prevent cardiovascular diseases like stroke, heart attack, and hypertension. The health benefits are many. This root can help with diarrhea, osteoporosis, asthma, arthritis, and allergies as well.
Medicinally, an important feature of Wasabi is that it contains compounds effective against some cancers. Extracts from Wasabi have been shown repeatedly to be effective against stomach cancer cells. Other types of cancer, including breast, fore-stomach and colon, may also be treated by compounds known to exist in Wasabi  but these have not yet been studied.
Compounds found in Wasabi are also effective when used in other medical situations. The isothiocyanates of Wasabi inhibit platelet aggregation  working as an effective anticoagulant. These anticoagulant properties could be used in the treatment of the elderly and during surgery where preventing platelet aggregation is vital.
If you grow other root vegetables, you might have fun growing this root. (Rose Marie Nichols McGee Nichols Garden Nursery suggests using a child’s wading pool filled with rich soil.) Put your container under shade cloth. Don’t forget holes for drainage. If your winters fall below 20ºF, you should mulch heavily, or bring the plants into a garage for winter. Alternatively, you could over-winter it in a hoop house or a cold-frame.
Wasabi Snack Peas Recipe
I love this spicy wasabi peas recipe! Not only are they good for you they are very tasty. Next time you have a party make up some of these instead of onion dip.
2 cups dried whole peas
2 tablespoons olive oil
4 teaspoons wasabi powder
2 tablespoons tahini
2 tablespoons rice vinegar
2 teaspoons Dijon mustard
Soak the peas covered in water overnight.
Preheat the oven to 200°F. Drain the peas, then cook them according to instructions on the package. Mix the olive oil with the cooked peas until well coated.
Oil a baking sheet and spread the peas evenly across it. Place in the oven and bake for 5 hours, until the peas appear dry and are crisp when bitten into.
Combine the wasabi powder, tahini, rice vinegar and mustard in a mixing bowl.
Combine the wasabi mixture with the hot peas making sure that all the peas are evenly coated.
Using a rubber spatula, spread the peas on the baking sheet, separating as many as you can. Increase the oven temperature to 250°F. Bake the peas for 10 to 15 minutes, until the coating is dry.
 "Science and Biomedical information about real Wasabi", Pacific Coast Wasabi
 Tanida N., Kawaura A., Takahashi A., Sawada K., and Shimoyama T. 1991. Suppressive effect of Wasabi on gastric carcinogenesis induced by MNNG in rats. Nutrition and Cancer, 16:53-58.
 Wattenberg L. W. 1977. Inhibition of carcinogenic effects of polycyclic hydrocarbons by benzyl isothiocyanate and related compounds. Journal of the National Cancer Institute, 58:395-398
 Kumagai H., Kashima N., Seki T., Sakurai H., Ishii K., and Ariga T. 1994. Analysis of volatile components in essential oil of upland Wasabi and their inhibitory effects on platelet aggregation. Bioscience Biotechnology and Biochemistry, 58:2131-2135.
Photo Credits: Many thanks to Doug Lambert, Real Wasabi, LLC and Chris Jones of FrogFarm Wasabi for information and permission to use their copyright photos. Wasabi & Ginger photo ©Juan Monino, iStockPhoto #4159401, Used by Permission; Wasabi Peas photo ©Anders Aagesen, iStockPhoto #3449151, Used by Permission.