URBAN PLANTER BOXES

Absolutely, over-fertilizing in the confined space of a planter box is not only possible but a common mistake. Unlike garden soil, potting mix in containers has limited volume. Excess salts from fertilizer accumulate quickly, creating a toxic environment for roots. This leads to "fertilizer burn," visible as brown, scorched leaf tips and edges, yellowing leaves, stunted growth, and sometimes a white crust on the soil surface. To fix an over-fertilized plant, immediately flush the soil by slowly running generous amounts of water through the drainage holes to leach out excess salts. You may need to repeat this. Trim away severely damaged foliage. Prevent future issues by always following label instructions, using a diluted, half-strength solution for container plants, and fertilizing only during active growth periods. Remember, in planter boxes, less is often more when it comes to plant food.