Once the water starts seeping out of the overflow drain hole the reservoir is full. Always make sure there is a clear passage way out of the drainage hole to ensure water can escape.
The Overflow drain hole is manufactured/pre-drilled in all of our window boxes and Patio Planters.
Our Tall Planters require you to drill your own drainage hole. The hole is not pre-drilled in our tall planters so you can use it indoors if you would like.
Window Box Overflow Drain Hole
Patio Planter Overflow Drain Hole
Tall Planter Drainage Hole Placement