Mulch Depth & Coverage Guide
By Vinod Kondeti · Updated
Depth is the biggest factor in how far your mulch goes. Every bag covers (bag cu ft × 12) ÷ depth in inches square feet, so halving the depth doubles the coverage. Scotts recommends 3 inches for its standard mulch, which it says helps block weeds, and 2 inches for its finer Triple Shred.
How do I measure for a depth & coverage project?
- A 2 cu ft bag covers 24 ft² at 1 in, 12 ft² at 2 in, 8 ft² at 3 in and 6 ft² at 4 in.
- Already have mulch down? Measure the existing layer and only add the difference.
- Follow the depth on your product's label first, then use this page to plan the quantity.
How is the depth & coverage amount calculated?
- Cubic feet = length × width × (depth in inches ÷ 12)
- Cubic yards = ft³ ÷ 27
- Bags = ft³ ÷ bag size (ft³), rounded up
- One bag covers (bag ft³ × 12) ÷ depth (in) square feet; 1 yd³ covers 324 ÷ depth (in) ft²
- Extra for waste/settling: volume × (1 + % ÷ 100)
- Round bed: π × (d ÷ 2)²; tree ring: π ÷ 4 × (outer² − inner²)
- Bulk cost = yd³ × $/yd³ + delivery; bag cost = bags × $/bag
Depth & coverage calculator questions
How much does a 2 cu ft bag of mulch cover?
At 3 inches, 8 ft². At 2 inches, 12 ft².
How deep should mulch be?
Scotts recommends 3 inches for its standard mulch and 2 inches for Triple Shred. Check your product label.
Sources
Estimates only. Use the coverage or bag size printed on your product. Read the mulch guide for worked examples.
More mulch calculators
- Mulch calculator (main)
- Mulch bags calculator
- Cubic yards calculator
- Tree ring calculator
- Round bed calculator
- Multiple beds calculator
- Gravel calculator
- Topsoil calculator