Winter can be tough on urban planter boxes, especially when they are exposed to rain, snow, and fluctuating temperatures. Moisture trapped inside the material expands when it freezes, causing cracks and structural failure. Here’s how to protect your investment and keep your planter boxes looking great all winter long.
First, focus on drainage. Before the first freeze, remove any saucers or trays that sit under the planters, as standing water is the main cause of freeze damage. Elevate your planter boxes on bricks or rubber feet to allow air circulation and prevent water from pooling underneath.
Next, consider insulation. For ceramic, terra cotta, or concrete planters, wrap the outside with bubble wrap or burlap. This layer buffers extreme temperature swings. If your planter boxes remain outdoors, use insulation foam boards placed inside the planter—away from the soil—to protect the inner walls.
If your planters contain live perennials or shrubs, move them to a sheltered location like against a south-facing wall or under an overhang. Alternatively, transport them into a cool garage or basement. For empty planters, cover them with waterproof fabric but leave a small opening for airflow to prevent mold.
For plastic or fiberglass planter boxes, the risk is lower, but they can still become brittle in severe cold. Empty them of soil and store upside down in a dry, covered area. If they are too large to move, wrap them in frost cloth and ensure no water collects inside.
Finally, avoid salt-based deicers near your planters. Many deicing chemicals can corrode metal finishes or degrade the glaze on ceramic boxes. Use sand or kitty litter for traction instead.
By following these winterizing steps, you can extend the life of your urban planter boxes and ensure they are ready for spring planting. A little preparation goes a long way in preventing expensive damage.