60 although providing perforations in a funnel and inserting the funnel in an inverted position into a container is the preferred way of fabricating the plant growing system 10 other fabrication methods are contemplated for instance providing a funnel in a porous material allowing air circulation therethrough is another alternative in accordance with the present invention the aeration device 14 advantages the bottom part of the plant growing system 10 and thus optimizes the root development through the substrate volume of the container 12 an appropriate ratio between the varying diameter of the flared portion 40 and the diameter of the container 12 must be selected in order to effectively provide a homogeneous concentration of air in the substrate 60 also the slope of the flared portion 40 must be wisely chosen for a fixed density of perforations 52 in the peripheral wall 44 a small slope will allow less oxygenation than an important slope an important slope will lead to a larger portion of the container 12 being occupied by the aeration device 14 whereby less substrate 60 can be retained in the container 12 it is therefore important to adapt the aeration device 14 in order to efficiently provide air to the substrate 60 the density of the perforations 52 in the peripheral wall 44 of the aeration device.