There is provided a planting base, a planting body, a planting system, and a planting method capable of effectively supplying water to the entire region of a greening target area. For that purpose, a planting body 10A is composed of a planting base 1B in which intersected groove lines 11b and 12b are formed on one surface and a water-impermeable layer 2 is formed on the bottom surface of the groove line, and a plant layer 4 which is fixed to a surface on which a groove line of the planting base 1B is formed and has a pre-grown ground cover plant 41. A water supply pipe 5 is buried in the groove line 11b to form a planting system 100.