PROBLEM TO BE SOLVED: To control the amount of drained water in the interior of a container for horticulture as required, and simultaneously to supply a sufficient amount of open air to the roots of a plant in the container for the horticulture. SOLUTION: A protrusion part 11 of the article laid on the bottom for the horticulture has a hollow and nearly cone shape, and belt-shaped draining parts 11A, 11B, 11C, 11D and 11E arranged in several steps at a nearly constant interval in the height direction, and extending in the circumference direction. The protrusion part 11 has many trapezoid small holes 11a, 11b, 11c, 11d and 11e arranged so as to closely contact with each other over the whole length in the circumference direction of the draining part at each step. A flat plate part 12 is formed into a nearly ring plate shape, and has several ring-shaped draining parts 12A, 12B and 12C arranged at a nearly constant interval in the radial direction, and extending in the circumference direction. Further the flat part 12 has many trapezoid small holes 12a, 12b and 12c extending in the inner direction of the radial direction over the whole circumference direction of the draining part at each step.
