Continuous tapestry of helophyte plants with ballast for semi-submerged use in wastewater treatment. The present invention describes a plant carpet of helophyte plants, e.g. Ex. Enea or espadaºa (typha l.), with a ballast, for its use in the purification of wastewater, and its method of obtaining it. The tapestry is formed by the rhizosphere of the plants intimately linked to the ballast, which remains semi-submerged in a wetland where the wastewater circulates. The semi-submerged carpet is achieved by controlled growth of the helofites with the ballast, which can be a mixture of sand and/or gravel in topsoil, and which serves to prevent the carpet from floating on the surface of the wetland. Oxygen for the degradation of organic matter is thus achieved by air diffusion through the water surface of the wetland and by means of the helofites that transport it through the specialized tissue of its aerenchyma to the rhizosphere, where an abundant microbial flora that uses said oxygen to degrade organic matter. (Machine-translation by Google Translate, not legally binding)