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Mulch Bed Calculator · Free calculator

20x24 Mulch Bed Calculator

Mulching a 20' × 24' bed (480 sq ft) 3" deep takes 4.67 cubic yards — 63 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 20x24.

Quick answer

3" deep (standard)
4.67 yd³
2 cu ft bags @ 3"
63
2 cu ft bags @ 2"
42
Bags cost @ 3"
$252
Bulk cost @ 3"
$190
Edging
88 LF

▍Mulch Calculator

Material
ft
in
ft
in
in
Waste Factor
$
L = 24' 0"W = 20' 0"D = 3"
Cubic Yards
4.67yd³
incl. 5% waste · Bulk delivery: order 4.75 yd³
Cubic Feet
126.00ft³
Area
480.0sq ft
Weight
1.40tons
Weight
2,800lbs
Mulch bags needed
  • 2 cu ft bag (2 ft³ yield)63

Mulch for a 20x24 bed by depth

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

DepthUseCubic yards2 cu ft bagsBags $Bulk $Weight
2"Refresh existing bed3.11 yd³42$168$1301,867 lbs
3"Standard (weed control)4.67 yd³63$252$1902,800 lbs
4"New bed / heavy weeds6.22 yd³84$336$2503,733 lbs

Bed prep for 20x24

ItemQuantityNotes
Landscape fabric (3' × 50' rolls)4528 sq ft incl. 10% overlap
Bed edging (20' sections)588 LF perimeter
Fabric staples54~1 per 9 sq ft
Pickup loads (≈2.5 yd³)2bulk mulch @ 3"

How the math works

  1. Area: 24 ft × 20 ft = 480 sq ft
  2. Volume @ 3": 480 × (3 ÷ 12) = 120.00 cu ft
  3. Add 5%: 120.00 × 1.05 = 126.00 cu ft
  4. Cubic yards: 126.00 ÷ 27 = 4.67 yd³
  5. Bags: 126.00 ÷ 2 cu ft = 63 bags

Trade pro tips

  • 4.67 yd³ at 3" — bulk delivery will be cheaper than bags.
  • 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 20x24 area?

At 3" deep, 63 bags of 2 cu ft mulch. At 2": 42 bags. At 4": 84 bags. All include 5% extra for 480 sq ft.

How many yards of mulch for 20x24?

2": 3.11 yd³; 3": 4.67 yd³; 4": 6.22 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 20x24 bed?

At 3": about $252 in bags or $190 in bulk before delivery. Bulk is usually cheaper at this size.

How much does the mulch for 20x24 weigh?

About 2,800 lbs at 3" (mulch runs 400–800 lbs per yd³ depending on moisture). That's 1.9 half-ton pickup loads of bulk mulch.