As the growing season winds down, giving your urban planter boxes a thorough cleaning is one of the most important tasks for any city gardener. This end-of-season ritual is crucial for preventing disease, eliminating pests, and ensuring your plants have a healthy start next spring. Here is the best method to clean your planter boxes effectively.
First, completely empty the planter box. Remove any remaining annual plants, being sure to shake the soil from their roots back into the container. For perennial plants, carefully transplant them into a temporary pot if you plan to reuse the planter. Discard any old, used soil; it is often depleted of nutrients and may harbor pathogens. Do not reuse it for your next planting.
Next, it's time to scrub. Use a stiff-bristled brush and a mixture of warm water and dish soap or a vinegar solution (one part vinegar to four parts water) to scrub the entire interior and exterior of the planter. Pay special attention to the corners and any mineral deposits or algae growth. The goal is to remove all dirt and debris. For tougher stains on materials like plastic or fiberglass, a mild bleach solution (one part bleach to nine parts water) can be used, but always wear gloves and work in a well-ventilated area.
After scrubbing, a disinfecting rinse is highly recommended. This final step kills any lingering fungal spores or bacteria. You can use the mild bleach solution mentioned above or a commercial horticultural disinfectant. Spray or wipe the solution over the entire planter, let it sit for 10-15 minutes, and then rinse thoroughly with clean water.
Finally, allow the planter box to air dry completely in the sun before storing it for the winter. If you live in a harsh winter climate, store the clean, dry planters in a garage or shed to protect them from cracking due to freeze-thaw cycles. By following these simple steps, you are investing in the long-term health of your container garden and setting the stage for another successful and beautiful growing season.