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Mulch Bed Calculator · Free calculator

10x12 Mulch Bed Calculator

Mulching a 10' × 12' bed (120 sq ft) 3" deep takes 1.17 cubic yards — 16 bags of 2 cu ft mulch with 5% extra. Here's 2", 3" and 4" depth, bag vs bulk cost and the fabric and edging for 10x12.

Quick answer

3" deep (standard)
1.17 yd³
2 cu ft bags @ 3"
16
2 cu ft bags @ 2"
11
Bags cost @ 3"
$64
Bulk cost @ 3"
$50
Edging
44 LF

▍Mulch Calculator

Material
ft
in
ft
in
in
Waste Factor
$
L = 12' 0"W = 10' 0"D = 3"
Cubic Yards
1.17yd³
incl. 5% waste · Bulk delivery: order 1.25 yd³
Cubic Feet
31.50ft³
Area
120.0sq ft
Weight
0.35tons
Weight
700lbs
Mulch bags needed
  • 2 cu ft bag (2 ft³ yield)16

Mulch for a 10x12 bed by depth

120 sq ft, 5% extra. Bags ~$4.00 (2 cu ft), bulk ~$40/yd³.

DepthUseCubic yards2 cu ft bagsBags $Bulk $Weight
2"Refresh existing bed0.78 yd³11$44$40467 lbs
3"Standard (weed control)1.17 yd³16$64$50700 lbs
4"New bed / heavy weeds1.56 yd³21$84$70933 lbs

Bed prep for 10x12

ItemQuantityNotes
Landscape fabric (3' × 50' rolls)1132 sq ft incl. 10% overlap
Bed edging (20' sections)344 LF perimeter
Fabric staples14~1 per 9 sq ft
Pickup loads (≈2.5 yd³)1bulk mulch @ 3"

How the math works

  1. Area: 12 ft × 10 ft = 120 sq ft
  2. Volume @ 3": 120 × (3 ÷ 12) = 30.00 cu ft
  3. Add 5%: 30.00 × 1.05 = 31.50 cu ft
  4. Cubic yards: 31.50 ÷ 27 = 1.17 yd³
  5. Bags: 31.50 ÷ 2 cu ft = 16 bags

Trade pro tips

  • 1.17 yd³ at 3" — bags are easier than bulk for this size.
  • Keep mulch 2"–3" away from trunks and siding — no "mulch volcanoes".
  • Refreshing an existing bed usually only needs 1"–2" on top.
  • One cubic yard of bulk mulch = 13.5 two-cu-ft bags.
  • A half-ton pickup carries 2–3 yd³ of mulch; a full-size bed with sides can take about 3.

Frequently asked questions

How many bags of mulch do I need for a 10x12 area?

At 3" deep, 16 bags of 2 cu ft mulch. At 2": 11 bags. At 4": 21 bags. All include 5% extra for 120 sq ft.

How many yards of mulch for 10x12?

2": 0.78 yd³; 3": 1.17 yd³; 4": 1.56 yd³. Bulk mulch is sold by the cubic yard; 1 yd³ = 13.5 bags of 2 cu ft.

How much does it cost to mulch a 10x12 bed?

At 3": about $64 in bags or $50 in bulk before delivery. Bags are usually simpler at this size.

How much does the mulch for 10x12 weigh?

About 700 lbs at 3" (mulch runs 400–800 lbs per yd³ depending on moisture). That's 0.5 half-ton pickup loads of bulk mulch.