How Much Mulch Do I Need?

The amount of mulch you need depends on the size of your garden beds and the depth you want to apply. Here's how to figure it out quickly.

The quick formula

Mulch needed (cu yd) = Length (ft) × Width (ft) × Depth (in) ÷ 324

Then multiply by 13.5 to convert cubic yards to 2 cu ft bags.

Step-by-step: how to measure your beds

Measure each bed — Walk the perimeter with a tape measure. Record length and width in feet. For curved beds, break them into rough rectangles.
Add up your areas — For multiple beds, measure each one separately and add them together.
Choose a depth — 2–3 inches is standard for existing beds; 3–4 inches for new beds.
Plug into the formula — Or use the Mulch Calculator to get bags and cubic yards instantly.

Coverage table — how far does 1 cubic yard go?

Depth	Coverage per cubic yard
1 inch	324 sq ft
2 inches	162 sq ft
3 inches	108 sq ft
4 inches	81 sq ft
6 inches	54 sq ft

1 cubic yard = 13.5 bags (2 cu ft each)

Coverage per bag (2 cu ft bag)

Depth	Coverage per bag
1 inch	24 sq ft
2 inches	12 sq ft
3 inches	8 sq ft
4 inches	6 sq ft

How much to buy: quick examples

Bed size	At 2” depth	At 3” depth
5 × 10 ft	4 bags	6 bags
10 × 10 ft	7 bags	10 bags
10 × 20 ft	13 bags	19 bags
20 × 20 ft	25 bags	38 bags

Rounded up. Assumes no waste factor — add 5–10% for irregular shapes.

Bags vs. bulk: which should you buy?

Under 1 cubic yard (13 bags): bags from a garden center are usually more convenient.
1–3 cubic yards: compare bag cost vs. bulk delivery — bulk often wins above 1.5 yards.
Over 3 cubic yards: bulk delivery is almost always cheaper and less work.

How much does mulch cost?

Bagged mulch typically runs $4–$8 per 2 cu ft bag at big-box stores. Bulk delivery varies by region: $25–$60 per cubic yard is typical. Enter your local price into the Mulch Calculator for a cost estimate.

Frequently Asked Questions

How many bags of mulch do I need for a 10×10 garden bed?

A 10×10 ft bed (100 sq ft) at 3 inches deep needs about 0.93 cubic yards or 13 bags (2 cu ft each), before adding a waste factor. Round up to 14 bags to be safe.

How deep should I apply mulch?

Apply 2–3 inches for existing beds that already have some mulch, or 3–4 inches for new beds or areas where weed suppression is a priority. Avoid piling mulch against plant stems.

How much does a bag of mulch cover?

A standard 2 cubic foot bag covers 24 sq ft at 1 inch deep, 12 sq ft at 2 inches, or 8 sq ft at 3 inches.

How many bags of mulch are in a cubic yard?

There are 13.5 bags (2 cu ft each) in one cubic yard. If you need more than 2–3 cubic yards, bulk delivery is usually cheaper.

Should I buy bags or bulk mulch?

Bags are convenient for small areas (under 1–2 cubic yards) or where a truck cannot access. Bulk delivery is significantly cheaper per cubic yard for larger projects.