The basic formula
Mulch is sold by the cubic yard, and coverage depends entirely on how deep you spread it. The formula is simple: square footage of the bed, multiplied by depth in feet, equals cubic feet needed. Divide by 27 (the number of cubic feet in a cubic yard) to get cubic yards.
| Depth | Coverage per cubic yard |
|---|---|
| 2 inches | ~160 sq ft |
| 3 inches | ~100 sq ft |
| 4 inches | ~80 sq ft |
For most beds, 2 to 3 inches is the right target — enough to suppress weeds and retain moisture without smothering roots or holding excess water against Georgia clay. See our mulch volcano article for what happens when depth gets pushed too far near tree trunks.
Measuring your beds
For a rectangular bed, multiply length by width. For an irregular or curved bed, break it into rough rectangles and triangles, measure each, and add them together — close enough is fine for ordering purposes since installers round up slightly anyway. Do not measure from a satellite photo if you can avoid it; aerial measurements are routinely off by 10 percent or more once tree canopy and shadow are accounted for.
Worked examples
| Bed size | Depth | Cubic yards needed |
|---|---|---|
| 100 sq ft (single foundation bed) | 3″ | ~1 cu yd |
| 300 sq ft (front yard bed set) | 3″ | ~3 cu yd |
| 600 sq ft (larger property, multiple beds) | 3″ | ~6 cu yd |
| 1,000 sq ft (whole-property refresh) | 2.5″ | ~8 cu yd |
Pine straw math is different
Pine straw is sold and measured by the bale, not the cubic yard. One bale covers roughly 35 to 45 square feet at a proper loose 3-inch depth, depending on how tightly it was baled. A typical 200 to 300 square foot bed needs 5 to 8 bales. See pine straw installation for full pricing.
What happens if you order too little or too much
Too little mulch spread thin does not suppress weeds through a full season and looks patchy almost immediately. Too much mulch piled deep smothers roots, holds excess moisture against Georgia's already slow-draining clay, and wastes money on material that is not doing any additional useful work past about 3 to 4 inches. The sweet spot for most beds is genuinely narrow, which is why measuring properly upfront saves both a return trip and wasted material.
Let us do the math for you
Every mulch installation or bulk delivery estimate includes exact bed measurement and yardage calculation at no charge, so you never have to guess or round from a rough formula. Call or text a photo of your beds and we can often give you a ballpark number before we even arrive.