Each piece is treated for bugs, but may need re-treating every couple of years. The planters love water, so all plants can be watered directly in them. The creations are very durable and can go inside or outside. However, if the roots are going to be out in the direct sunlight and not on a covered patio, under an overhang, inside, or at least in the shade, we recommend using a wood sealer such as Thompson Water Seal or polyurethane.