This Irrigator is designed to sit on top of the GroVert Vertical Garden System to regulate the flow of water into the panel. It slowly and evenly distributes the water through the panel so you can quickly fill it up and walk away.
If you want to stack one GroVert panel on top of another, you can place the irrigator on the top one and just fill it up twice. The water will transfer from one panel to the next and both panels will get perfectly watered.
*Note this doesn't work on the GroVert Skinny. It only works on the GroVert Vertical Wall Garden.