If this is not possible, then it is necessary to provide a drainage layer with a thickness of 20-30 cm during planting.
Ọ bụrụ na nke a agaghị ekwe omume, mgbe ahụ, ịkwesịrị ilekọta ngwá ọrụ nke nnukwu mmiri drainage - na olulu ọdịda kwesịrị itinye akwa nkume 10-20-centimita nke gravel.