URBAN PLANTER BOXES

When you replant an urban planter box, you do not always need to throw away all the old soil. First, tip it out and inspect it. If it looks reasonably healthy and has no strong smell, mold, or obvious pest problem, screen out old roots, stones, and debris. Mix the old soil with fresh potting mix and compost so it regains structure and nutrients, then use it again in the same planter or in other containers. Avoid reusing old soil for the same plant family year after year, because that can increase disease and pest pressure. If the soil was affected by disease, pests, or poor drainage, do not put it straight back. You can solarize small amounts by sealing moist soil in a clear plastic bag in hot sun for several weeks, or dispose of it in sealed bags according to local rules. For food crops in urban areas, especially if the soil history is unknown, consider testing for lead or other contaminants before reuse. Never dump old soil into storm drains, alleys, or green spaces. The best approach is to reuse healthy soil with amendments, sterilize or discard problem soil responsibly, and refresh the planter with compost and fresh potting mix before replanting.