Figuring out how much soil you need for your new urban planter boxes is a simple math problem that can save you time, money, and a lot of heavy lifting. You don't need to be a gardening expert or a mathematician, just follow this straightforward process.
The key is to calculate the volume of your planter box. Volume is simply the amount of space inside your box, and it's measured in cubic feet or cubic meters when dealing with soil.
Here is the essential formula:
Volume = Length × Width × Depth
Step-by-Step Guide:
1. Measure Your Box: Using a tape measure, record the inside dimensions of your planter box.
* Length: Measure the longest side from one inner edge to the other.
* Width: Measure the shorter side from one inner edge to the other.
* Depth/Height: Measure from the bottom of the box to the top inner rim.
2. Do the Math: Multiply these three numbers together. Ensure all your measurements are in the same unit (e.g., all in feet or all in inches).
*Example:*
If your planter box is 4 feet long, 2 feet wide, and 1.5 feet deep, the calculation is:
4 ft (L) × 2 ft (W) × 1.5 ft (D) = 12 cubic feet
3. Convert from Inches to Feet (if necessary): If you measured in inches, you'll need to convert to feet first. Simply divide each measurement by 12.
*Example:*
A box that is 24 inches long, 12 inches wide, and 18 inches deep.
* Length: 24 inches / 12 = 2 feet
* Width: 12 inches / 12 = 1 foot
* Depth: 18 inches / 12 = 1.5 feet
* Volume: 2 ft × 1 ft × 1.5 ft = 3 cubic feet
How Much Soil to Buy:
Soil is typically sold by the cubic foot in bags. If your calculation shows you need 12 cubic feet of soil, you should purchase 12 cubic feet. It is often a good idea to buy a little extra (about 5-10%) to account for soil settling over time. For our example of 12 cubic feet, consider getting 13 cubic feet.
For larger projects, soil and compost may be sold by the cubic yard. There are 27 cubic feet in one cubic yard. If your total volume is more than 27 cubic feet, divide by 27 to see how many cubic yards you need.
By taking a few minutes to measure and calculate, you can ensure your urban garden gets off to the perfect start without any wasted soil or last-minute trips to the garden center.