PROBLEM TO BE SOLVED: To provide a separating bed for a vegetation, capable of effectively performing water discharge. SOLUTION: This separating bed for the vegetation by covering a water- penetrating sheet 5 toward a ditch 2 so that its cross section becomes U or V-shape, putting a medium into a recess formed thereby and cultivating plants 7 is characterized by having the water-penetrating sheet 5 exhibiting a higher transmittance of a light in its middle part 52 than in its left and right side parts 51, 53. The water-penetrating sheet may be a woven fabric obtained by weaving with a fine mesh at the left and right parts and with a coarse mesh at the middle part, or a plastic sheet obtained by boring fine holes in the left and right parts and relatively large size holes in the middle part.
