Build the frame with rot-resistant cedar and keep the soil inside a removable food-safe liner rather than directly against the boards. Provide several drainage holes and leave an air gap under the liner. Stainless or coated exterior screws prevent dark rust stains. Slats should have small, even gaps for ventilation but still conceal the container. Seal only with an exterior finish labeled suitable for planters, and coat all end grain thoroughly. Before filling, confirm the balcony can safely carry the saturated weight of soil and water.
Log in to leave a comment.