That's an excellent question! Filling your planter box with the correct amount of soil is crucial for your plants' health and growth. For our medium-sized urban planter box, calculating the soil you need is straightforward.
First, you'll need to know the dimensions of your specific planter box. A typical medium planter might be around 24 inches in length, 12 inches in width, and 12 inches in height.
The formula to calculate the soil volume is:
Length x Width x Height = Volume in Cubic Inches
Using our example:
24 inches (L) x 12 inches (W) x 12 inches (H) = 3,456 cubic inches.
To convert this into cubic feet (which is how bagged soil is typically sold), simply divide the cubic inches by 1,728 (the number of cubic inches in a cubic foot).
3,456 ÷ 1,728 = 2 cubic feet.
Therefore, for this example, you would need 2 cubic feet of potting soil to fill your medium planter box. We always recommend using a high-quality potting mix, as it provides the right balance of drainage and moisture retention for container gardening. Happy planting