How Much Mulch Do I Need?
To figure how much mulch you need, measure the bed in feet and decide how deep to spread it, usually 3″. Enter both above and you get cubic yards and bags. A 10′ × 10′ bed at 3″ takes 0.93 cubic yards, or 13 bags of 2 cu ft.
Cubic yards = L (ft) × W (ft) × D (ft) ÷ 27 10′ × 10′ × (3″ ÷ 12) = 25 cu ft 25 cu ft ÷ 27 = 0.93 cu yd 25 cu ft ÷ 2 cu ft = 12.5, so 13 bags
Beds are rarely perfect rectangles. Use Circle for a round bed. For mulch around trees, use Ring: the outer diameter is the mulched circle, the inner one is the trunk. Then set How many. Five rings 6′ across around 1′ trunks, 3″ deep, take 1.27 cubic yards, or 18 bags of 2 cu ft.
For an odd-shaped bed, split it into pieces with Add another area, or pace off the square footage and use By area, for example 250.
Topping up last year’s mulch? Measure what’s left and enter only the depth you’re adding.
How Many Bags of Mulch in a Yard?
A yard of mulch is 27 cubic feet. Divide by the bag size: 18 bags of 1.5 cu ft, 13.5 bags of 2 cu ft (buy 14) or 9 bags of 3 cu ft.
| Bag size | Bags per cubic yard | 10′ × 10′ bed, 3″ deep |
|---|---|---|
| 1.5 cu ft | 18 | 17 |
| 2 cu ft | 13.5 (buy 14) | 13 |
| 3 cu ft | 9 | 9 |
Bag sizes from store listings: 1.5 cu ft Scotts Earthgro at Home Depot, 2 cu ft Sta-Green at Lowe’s. 3 cu ft bags are less common; we didn’t find one at Home Depot or Lowe’s. Bag size sources
2 cu ft is the size you’ll find most often. Pick yours under Extra, bag size & prices; the calculator always rounds bags up.
Mulch is light. A cubic yard of wood chips weighs around 500 lb, anywhere from about 250 to 800 lb depending on how wet it is (EPA; Washington Dept. of Ecology). That swing is why we don’t show a weight for mulch.
How Much Does a Yard of Mulch Cover?
A cubic yard of mulch covers 108 sq ft at 3″ deep and 162 sq ft at 2″. The thinner you spread it, the further it goes.
| Depth | 1 cubic yard covers | One 2 cu ft bag covers |
|---|---|---|
| 1″ | 324 sq ft | 24 sq ft |
| 2″ | 162 sq ft | 12 sq ft |
| 3″ | 108 sq ft | 8 sq ft |
| 4″ | 81 sq ft | 6 sq ft |
Coverage = cubic feet ÷ depth in feet. It works the same for mulch, topsoil or compost.
To go the other way, divide the bed area by the coverage. A 300 sq ft bed at 3″ needs 300 ÷ 108 = 2.78 cubic yards.
How Deep Should Mulch Be?
Spread bark or wood-chip mulch 2″ to 4″ deep. The calculator starts at 3″. Fine, double-shredded mulch goes on thinner, 1″ to 2″.
Keep mulch a few inches back from tree trunks and shrub stems, and don’t pile it against the bark.
These depths follow Penn State Extension, Clemson HGIC and The Morton Arboretum.
Topsoil Calculator
Topsoil works the same way: area times depth. Pick Topsoil in the material list and the depth changes to 6″, the usual figure for a new lawn.
| Job | Topsoil depth |
|---|---|
| New lawn | 4″ to 6″ |
| Raised bed | 6″ to 8″ |
| Top-dressing existing soil, worked in | 2″ to 3″ |
Penn State Extension (lawns), NC State Extension (raised beds), Michigan State University Extension (amending soil). Depth sources
A cubic yard of topsoil covers 81 sq ft at 4″ and 54 sq ft at 6″. Delivered moist, it weighs about 1.35 tons (2,700 lb); dry, closer to 1.1 tons. The calculator shows the moist weight, which is what goes in your truck.
A 4′ × 8′ raised bed filled 8″ deep takes 21.3 cubic feet. That’s 29 bags of 0.75 cu ft, or 0.79 cubic yards in bulk.
Bagged topsoil usually comes in 0.75 cu ft (40 lb) bags. A cubic yard is 36 of the 0.75 cu ft bags.
How Much Does Mulch Cost per Yard?
Bulk mulch runs $25 to $100 a cubic yard, with $40 typical, before delivery (HomeGuide, Apr 2025). A 2 cu ft bag of Sta-Green at Lowe’s is $3.98 (Oct 2026), and bags run $2 to $8 depending on the brand.
Per yard, bags cost more: 14 bags at $3.98 come to $55.72, against about $40 in bulk. Add a delivery fee, though, and bags can still come out ahead on a few small beds. For several yards, get a bulk quote.
Topsoil is different. At $3.99 for a 0.75 cu ft bag (Ace), a yard in bags costs $143.64. Bulk topsoil is $10 to $50 a yard, about $30 typical (HomeGuide; that page dates from Sep 2023, so prices may have moved). For a new lawn or more than a couple of raised beds, buy bulk.
Prices vary by region. Type yours under Extra, bag size & prices and the calculator compares bags and bulk for you.
Mulch and Topsoil Questions
Is a cubic yard the same as a yard?
Yes. When a garden center or landscape yard says a yard of mulch or soil, it means a cubic yard: 3′ × 3′ × 3′, or 27 cubic feet. A square yard is flat, 9 sq ft, and doesn’t measure volume.
How much dirt is a cubic yard?
27 cubic feet. Moist topsoil at that volume weighs about 1.35 tons and covers 81 sq ft at 4″ deep. In bags, it’s 36 bags of 0.75 cu ft.
How many cubic feet are in a yard of mulch?
27. A cubic yard is 3 ft long, 3 ft wide and 3 ft deep.
How many bags of mulch is 1 yard?
13.5 bags of 2 cu ft, so buy 14. With 1.5 cu ft bags it’s 18, and with 3 cu ft bags it’s 9.
How much mulch is in a bag?
The volume is printed on the bag. Most are 2 cu ft; 1.5 cu ft is also common. A 2 cu ft bag covers 8 sq ft at 3″ deep, or 12 sq ft at 2″.