Creating a thriving outdoor plant box in a coastal climate can be challenging due to salty air, strong winds, and sandy soil. However, selecting the right salt-tolerant plants ensures a lush and vibrant display. Here are the best options for your coastal garden:

1. Sea Thrift (Armeria maritima) – This hardy perennial produces pink or white blooms and thrives in sandy, well-drained soil. Its compact size makes it perfect for plant boxes.

2. Lavender (Lavandula) – Known for its fragrant purple flowers, lavender is drought-resistant and tolerates salty conditions, making it ideal for coastal settings.

3. Sedum (Stonecrop) – These succulents are low-maintenance and excel in dry, windy environments. Their fleshy leaves retain moisture, reducing watering needs.

4. Festuca Grass (Blue Fescue) – Ornamental grasses like Festuca add texture and movement to plant boxes while resisting salt spray and poor soil.

5. Rosemary (Rosmarinus officinalis) – A versatile herb, rosemary thrives in coastal climates, offering aromatic foliage and blue flowers.

For best results, ensure proper drainage and occasional rinsing of leaves to remove salt buildup. With these resilient plants, your coastal plant box will flourish year-round.