Creating a natural privacy screen in an outdoor plant box is a stylish and eco-friendly way to enhance your garden or balcony. The best plants for this purpose combine height, density, and low maintenance. Here are top choices:

1. Arborvitae (Thuja spp.) – A classic evergreen with dense foliage, perfect for year-round privacy. It grows tall and narrow, ideal for small spaces.

2. Bamboo (Phyllostachys spp.) – Fast-growing and tall, bamboo forms a thick screen quickly. Opt for clumping varieties to avoid invasiveness.

3. Boxwood (Buxus spp.) – A versatile shrub that can be trimmed into neat hedges, offering both privacy and aesthetic appeal.

4. Privet (Ligustrum spp.) – Hardy and fast-growing, privet hedges provide excellent coverage and can tolerate frequent pruning.

5. Holly (Ilex spp.) – With its spiky leaves and dense growth, holly adds privacy while deterring intruders.

For a layered look, mix tall plants like bamboo with mid-height shrubs such as boxwood. Ensure proper spacing and regular watering to maintain healthy growth. These plants will transform your outdoor plant box into a lush, private retreat.