How much mulch do I need?

How Much Mulch Do I Need? (Simple Guide)
Mulch is one of the easiest ways to improve your garden. It helps retain moisture, suppress weeds, and makes your beds look beautiful. But how much do you actually need?
Use this quick guide to calculate the right amount.
Measure Your Area
First, measure the length and width of each area you plan to mulch. Multiply them to get the square footage.
Example:
- Length: 20 feet
- Width: 5 feet
20 × 5 = 100 square feet
Choose Your Depth
For most gardens, 2–3 inches of top-dressed organic matter is ideal.
- 2 inches: Light coverage, good for beds with existing organic material.
- 3 inches: Best for new beds or areas with lots of weeds.
Use This Formula to Calculate Mulch Volume.
Here’s the simple mulch formula:
Cubic Yards=Square Feet×Depth (in inches)324\text{Cubic Yards} = \frac{\text{Square Feet} × \text{Depth (in inches)}}{324}
Example:
100 sq ft × 3 inches deep:
=100×3324=0.93cubicyards= \frac{100 × 3}{324} = 0.93 cubic yards
Round up to 1 cubic yard.
For more continuing education math instruction, try this channel.
Quick Reference Chart
Square Feet | 2 Inches Deep | 3 Inches Deep |
---|---|---|
100 sq ft | 0.6 cu yd | 0.9 cu yd |
200 sq ft | 1.2 cu yd | 1.8 cu yd |
500 sq ft | 3.1 cu yd | 4.6 cu yd |
1,000 sq ft | 6.2 cu yd | 9.3 cu yd |
Mulch Ordering Tips.
- This material is sold by the cubic yard.
- 1 cubic yard = about 13–14 standard bags (2 cu ft each).
- Always order a little extra to account for settling.
Final Thoughts on Mulch Volume.
Calculating how much material you need doesn’t have to be hard. Measure your beds, choose your depth, and use the formula or chart above to plan your project.

Note: the Jessecology standard procedure is to sub organic compost for mulch on most projects. This practice is better for the health of the localized garden and in turn the ecosystem at large.