Filling large urban planter boxes is an exciting step in creating your green oasis. However, the cost of soil can be surprising if you don't plan ahead. The final price depends on three key factors: the volume of your planters, the type of soil you choose, and how you buy it.
First, calculate the soil volume you need. For a rectangular planter box, use this formula: Length (ft) x Width (ft) x Depth (ft) = Volume in cubic feet (cu ft). For example, a 6ft long, 2ft wide, and 1.5ft deep planter requires 6 x 2 x 1.5 = 18 cubic feet of soil. Repeat this for each box and add the volumes together for your total need.
Next, understand soil types and costs. Basic topsoil is the most affordable, often ranging from $2 to $5 per cubic foot, but it may need amendment for optimal plant growth. Premium potting mix or raised bed soil, which is well-draining and nutrient-rich, typically costs between $5 and $15 per cubic foot. For edible plants, investing in a high-quality mix is recommended.
Finally, consider your purchasing option. Buying bags (usually 1-2 cu ft each) is convenient for small volumes but becomes expensive for large projects. For anything over 20 cubic feet, purchasing in bulk by the cubic yard (1 cubic yard = 27 cubic feet) is far more cost-effective. You'll need to factor in a delivery fee for bulk soil, but the savings per cubic foot are significant.
As a rough estimate, filling a single large planter box (15-25 cu ft) with bagged premium soil could cost $150 to $400. For multiple boxes, getting a quote for bulk delivery will likely cut that cost substantially. Contact local garden centers or soil suppliers for the most accurate pricing based on your specific project size.