PROBLEM TO BE SOLVED: To provide a revolutionary Japanese horseradish cultivation plant demonstrating an unconventional action effect.SOLUTION: This Japanese horseradish cultivation plant for cultivating Japanese horseradish 1 includes a greenhouse cultivation portion 5 constructed by covering the upper side of each of a plurality of cultivation areas 3 provided in a soil region 2 with a covering body 4. Each of the greenhouse cultivation portions 5 is installed with a watering portion 7 watering cultivation water W, and a drainage portion 8 draining the cultivation water W watered from the watering portion 7 to the outside of the greenhouse cultivation portion 5. The drainage portion 8 of one greenhouse cultivation portion 5 and the watering portion 7 of another greenhouse cultivation portion 5 among the greenhouse cultivation portions 5 adjacent to each other are connected with each other so as to supply the cultivation water W from the drainage portion 8 of the one greenhouse cultivation portion 5 to the watering portion 7 of the other greenhouse cultivation portion 5.
