Figuring out how much soil you need for your urban planter boxes is a straightforward process that can save you time, money, and a lot of heavy lifting. The key is to calculate the volume of each planter box. Don't worry; the math is simple.
Here is the essential formula you will use:
Volume (in cubic feet) = Length (ft) x Width (ft) x Depth (ft)
If you measured your planter in inches, simply divide each measurement by 12 to convert it to feet first. For example, a box that is 24 inches long, 12 inches wide, and 12 inches deep would be calculated as follows:
* Length: 24 inches / 12 = 2 feet
* Width: 12 inches / 12 = 1 foot
* Depth: 12 inches / 12 = 1 foot
* Volume = 2 ft x 1 ft x 1 ft = 2 cubic feet.
Step-by-Step Guide:
1. Measure Your Boxes: Grab a tape measure and record the internal length, width, and depth (or height) of every planter box you need to fill. Using the internal dimensions is more accurate.
2. Calculate Individual Volumes: Use the formula above for each unique box size. If you have multiple boxes of the same size, calculate the volume for one and then multiply by the number of boxes.
3. Add It All Up: Sum the volumes of all your planter boxes to get your total soil requirement in cubic feet.
Putting It into Practice:
Let's say you have two planter boxes:
* Box 1: 4 feet long, 2 feet wide, 1.5 feet deep. Volume = 4 x 2 x 1.5 = 12 cubic feet.
* Box 2: 2 feet long, 2 feet wide, 1 foot deep. Volume = 2 x 2 x 1 = 4 cubic feet.
* Total Soil Needed: 12 + 4 = 16 cubic feet.
Buying Your Soil:
Soil and potting mix are typically sold by the cubic foot in bags (e.g., 1 cu ft, 1.5 cu ft, 2 cu ft) or by the cubic yard from landscaping suppliers. One cubic yard equals 27 cubic feet. For our example of 16 cubic feet, you would need to buy 16 one-cubic-foot bags. If your total is a larger number, like 40 cubic feet, it might be more economical to buy 1.5 cubic yards (which is 40.5 cubic feet) from a bulk supplier.
Pro Tips:
* Account for Settling: Soil compacts over time. It's often a good idea to add an extra 5-10% to your total volume to account for this settling.
* Don't Fill to the Brim: Remember, you don't usually fill the planter to the very top with soil; leave an inch or two for watering. You can factor this in by slightly reducing your depth measurement.
* Use an Online Calculator: If math isn't your favorite, a quick search for a "soil volume calculator" can do the work for you.
By following these simple steps, you can purchase the perfect amount of soil for your urban garden, ensuring your plants have a great foundation without any wasted expense or effort.