The invention relates to a planting method of a rhizome plant and a planting box. A principle thereof is as follows: the pressure of soil on rhizomes of plants is reduced, and the rhizomes of plants grow without outer soil pressure. The method comprises the following steps: the planting box is imbedded in ground surface; the side wall of the planting box is evenly distributed with pores; the rhizome plants are planted at the side of the planting box; the root of the rhizome plant passes through the pores and pierces into the planting box and grows in the planting box; the planting box is provided with a box cover which can be opened to observe the growth condition inside the planting box; and management, fertilization and pick are carried out. The lowest height of the pores on the side wall of the planting box is higher than the box bottom; the box bottom is hermetic and can store a certain water and fertile to reduce the number of times for watering and fertilizing; and the soil is added at the height, and the upper part of the soil is empty or is used for placing light foam materials. When the root of plant passes through the pores to penetrate into the box, the rhizome left in the box can grow at the sate of no soil pressure, and under the condition, the root of plant can grow larger.