How to Calculate How Much Mulch You Need

You don’t need advanced math—just a few simple steps.

Step 1: Measure the Area

Multiply length × width to get square footage.

Step 2: Choose the Right Depth

• 2 inches for most beds
• 3 inches where weed pressure is high

Step 3: Use the Standard Formula

Square feet × depth (in inches) ÷ 324 = cubic yards needed

If you’re buying bagged mulch, a standard 2-cubic-foot bag covers about 12 square feet at 2 inches.

Common Garden Sizes: What to Buy

• 10 × 10 ft bed (100 sq ft)
  • 2 inches: ~0.17 cu yd (5–6 bags)
  • 3 inches: ~0.25 cu yd (7–8 bags)
• 500 sq ft garden area
  • 2 inches: ~0.85 cu yd
  • 3 inches: ~1.25 cu yd
• 1,000 sq ft landscape bed
  • 2 inches: ~1.7 cu yd
  • 3 inches: ~2.5 cu yd

Buying slightly extra is fine—but spreading all of it isn’t always wise.