I managed to find three Wasabi plants off Trademe. The are the real ones, not Horseradish. I so far have managed to keep them alive but they are not thriving. They should be growing in stoney 'soil', with 70 % shade.....along a stream, but I dont have one. Mine are growing in the tallest pots I could find with gravel at the bottom and tucked under my ferns that just happen to be under the pipe running to the water tank. I have been able to shift the pipe that runs to the tank just enough to allow some rain water to fall down onto these plants. That works at keeping them hydrated so long as it is actually raining....which it hasnt done for some time..... so I have been hand watering from above the ferns. So far they are all still alive but I need to work out a better system for them in order to get them big enough so I can get a crop from them. Interestingly, I found out recently that the tubes of Wasabi often have horseradish as the main ingredient, dont know if that is true or not.. So now I am thinking of looking for that to see if it has the same Zing as Wasabi, might be easier to grow and I might actually have something homegrown to put on my sushi.