Calculating Soil For Planter Box. Calculate both the volume and the cost of the topsoil needed. This is the same math formula as calculating the volume of the planter box.
The weight of soil can vary enormously based on the volume of water it contains. That will get your soil in the ballpark. How much soil to purchase depends upon the depth and size of your garden bed.
Input the length (a), width (b) and height (c) of your space to our topsoil calculator to find the volume in m³.
This article will take you through all of the math, step by step so it won't hurt a. Knowing how much garden soil to buy to fill your planter box requires that you calculate the cubic feet that it can hold. If you want to grow a fruit tree in a planter or container, you will need to make sure it is big enough for the tree. In the above example, you'd multiply 3.33 by 10 to get 33.33 cubic feet.