Layering propagation device for selenium-rich apples planted in cold region and planting method of selenium-rich apples

The invention provides a layering propagation device for selenium-rich apples planted in a cold region and a planting method thereof, the layering propagation device comprises a first shell and a second shell, and positioning columns which are movably sleeved in the second shell and are symmetrically distributed are arranged on one side of the first shell. According to the layering propagation device for the selenium-rich apples planted in the cold region and the planting method of the selenium-rich apples, the first shell is made of a transparent material, so that after the first shell and the second shell are closed, under the premise that the shells do not need to be opened, the conditions of sprouting root systems of branches at girdling positions on the inner sides of the shells can be directly observed through the second shell; meanwhile, when the first shell and the second shell are closed, the first shell is located at the shady position, the second shell is located at the sunny position, at the momen