Figuring out the correct quantity of mulch for your landscape is the most important step towards a successful project. If you order too little mulch, you will need to order more, paying additional delivery fees, or your gardens will remain unfinished and your soil unprotected. Order too much, you will have spent more than necessary and you will be begging your neighbor to take the extra mulch off your hands. In this guide, you will learn the right ways to calculate exactly how much mulch you need for your gardens.
What is a Cubic Yard?
When buying mulch in bulk, the most common measurement is in cubic yards. A cubic yard (yd3) is the volume that fits within a cube three feet wide, three feet long, and three feet tall. One cubic yard is equivalent to 27 cubic feet.
Landscape supply yards measure a cubic yard of mulch by the scoop. It is important to ask the supply yard you plan to work with if their loader’s bucket measures a full cubic yard. Some sell scoops that are less than a cubic yard. Mulch Pros Landscape Supply guarantees that you receive a full cubic yard with each scoop of mulch.
One cubic yard of mulch will spread 108 square feet at 3 inches thick, 162 square feet at 2 inches thick, and 324 square feet at only 1 inch thick.
Measuring Gardens to Calculate Mulch Needs
There are various ways to estimate how many cubic yards of mulch you will need to order. Some people will prefer one method versus another, however, accuracy will vary depending on the method used. The methods we will cover in this guide are, listed in order of accuracy:
- Using our Mulch Calculator with Manual Measurements – Most Accurate
- Measuring Areas with Aerial Imagery
- Converting Bags to Cubic Yards Using Records From Previous Mulching
- Eyeballing It – Least Accurate
Mulch Calculator with Manual Measurements
This method is the most accurate way to measure for your mulch order. You will measure with a measuring tape or measuring wheel and round to the nearest foot.
Many gardens are irregularly shaped. To handle this, break up the garden into easy to measure rectangles, triangles and circles. Don’t stress about the math! Our easy to use Mulch Calculator will do all the geometry and calculations for you.
Mulch Calculator Steps:
- Give the area you are measuring a label for later reference.
- Tell the calculator if the shape you are measuring is a rectangle, triangle, or circle. You can also choose to simply input the area in square feet if you’d like.
- Input the required dimensions feet (rounded). The calculator will ask for the appropriate dimensions based on the shape you selected in the previous step.
- Select how thick you plan to spread the mulch. We recommend three inches when starting from bare dirt, two inches for normal installations, or one inch for a very light refresh.
- Click ‘Add Row’ to calculate and add the row to your total area table.
Aerial Imagery Mulch Calculator
Measure your mulch needs on your computer by simply clicking to draw shapes around your garden areas! This method will likely be the favorite method of anyone who loves technology. Aerial imagery continues to get better and better as technology advances. Aerial images vary from photos taken from satellites out in space to low flying aircraft that take high-resolution photos of the ground below. Areas with higher population density tend to be areas with the best quality aerial images. While this method can be VERY accurate, there are important obstacles that can make using this method ineffective.
Do NOT use this method if:
- Your property has a lot of overhead trees that will block the view of the garden edges.
- Your property has had significant changes since the latest image was captured. This includes most new construction homes.
- Your garden areas are very steep. The satellite calculator assumes the ground is flat. Steep areas will be underestimated.
This method is BEST for properties that are:
- Generally open with few large tree canopies overhead.
- Unchanged since the last aerial image was captured.
- Somewhat flat to gentle hills.
Mulch Bags to Cubic Yards Calculator
If you have previously purchased mulch in bags for your garden and have records of how many were used, you can convert that into cubic yards. It is important to remember mulch depth is extremely important to include in your measurement. If you want your mulch to spread two times thicker than previous, you will need to order twice the volume.
Most bags of mulch come in 2 cubic foot volume, however some can be larger or smaller. 1 cubic yard equals 27 cubic feet, therefore 1 cubic yard equals 13.5 bags of mulch (2 ft3/bag).
While this method will not be as accurate as using accurate measurements, it is handy to get a general ballpark estimate of cubic yards needed. Our Mulch Bags to Cubic Yards Conversion Calculator will do the math for you!
While many landscapers use this method from their years of experience, it is not recommended for any homeowner. Contractors who eyeball their ‘measurements’ are more likely to over or underestimate than are homeowners that use the recommended measuring methods.
The concept behind eyeball measurements is to visualize an area that is 10 feet long and 10 feet wide. This square is 100 square feet. Then to go through the yard counting how many 100 square foot areas there are. Each cubic yard covers roughly 100 square feet at 3 inches thick. Therefore if 16 hundred square foot sections were counted, the contractor would recommend 16 cubic yards.
There are several methods people can use to estimate their bulk mulch needs. Any of the above methods are better than outright guessing. Our overall recommendation is to use the Mulch Calculator with Manual Measurements. It is, however, only as good as the measurements you put in.
One last tip: Do not stress about measuring to the 100th decimal of one cubic yard. The reality is that you must order in whole cubic yards. While your measurements and the volume ordered and delivered may be accurate, it is up to the installer to spread the mulch to a consistent depth to ensure your order spreads as planned.
Which method worked for you? Do you know of another method? Please mention how you measured for your mulch order in the comments section.