This is a drawing from an Australian planter patent. (click to enlarge)
Note the transparent exterior funnel shaped fill tube. It serves as both a water level indicator and fill tube. I wonder if this is worth the extra manufacturing cost. A simple alternative for checking the water level is to stick a plastic tube pipette down the fill tube.
I do not know whether this planter has come to market in Australia or elsewhere. There are hundreds of planter utility patents that never make it off the drawing board and into the market. Selling the proverbial "better mousetrap" is much easier said than done.
A container (11) having upwardly and outwardly extending walls (12) from a base (13) to a rectangular open top (14) that can be covered by flexible top or lid and with walled shape includes ribbing for strength and for nestable stacking in delivery. The container to form a top section (21) above the platform (15) and a lower section (22) below the plate (16) and providing an air pocket between the plant material and plant growth material in the upper section and the water in the water reservoir in the lower section by providing outlet of water at a level just below the upper section; and maintaining water reservoir with inlets and outlets with restricted communication to the external environment such that mosquito ingress is prevented while providing a self watering gardening system with water overflow.