Every spring the same thing happens at garden centres: a car boot full of mulch bags, three beds done, and a trip back for more. Mulch is cheap; the second trip and the extra bags are not. Ten minutes with a tape measure fixes it. This guide covers measuring, bags against bulk, how deep to spread, what a yard weighs, and a plan for doing the whole yard in one morning.
Get the number for your beds
Add each bed, pick the material and depth, and get cubic yards, bags and weight. Works for mulch, topsoil, compost, gravel and sand.
Open the mulch calculatorThe only formula you need
Cubic yards = length (ft) x width (ft) x depth (inches) / 324
A 25 by 4 foot border at 3 inches deep is 25 x 4 x 3 / 324 = 0.93 cubic yards. Round beds use 3.14 x radius squared for the area. Odd shapes: split them into rectangles and circles and add them up.
How deep to spread
| Situation | Depth |
|---|---|
| Topping up an existing bed | 1 to 2 inches |
| Fresh mulch on bare soil | 3 inches |
| Weed control on open ground | 3 to 4 inches (cardboard underneath helps) |
| Around annuals and shallow-rooted perennials | 1 to 2 inches |
| Around trees | 3 inches in a wide ring, none touching the trunk |
| Playground wood chips | 6 to 9 inches for fall protection |
More is not better. Over 4 inches, mulch stays wet, roots grow up into it and it can smother shrubs. Keep it off the trunk of trees and off the siding of the house.
Bags or bulk
A cubic yard is 27 cubic feet: 13.5 bags of 2 cubic feet or 9 bags of 3 cubic feet. The break-even is usually around 10 bags. Below that, bags are convenient, stay dry and fit in a car. Above it, bulk by the yard is cheaper even with the delivery fee, and there is no plastic to dispose of.
| Need | Buy | Why |
|---|---|---|
| Under 0.5 yard (about 6 bags) | Bags | Cheap enough, no delivery charge |
| 0.5 to 1 yard (7 to 13 bags) | Either | Compare the delivered price per yard with the bag price x 13 |
| Over 1 yard | Bulk | Usually a third to half the price of bags |
Bulk suppliers charge a flat delivery fee within a radius, so order the whole season's material in one drop: mulch for the beds and topsoil for the lawn patches on the same truck.
What a cubic yard weighs
This matters if you plan to collect it yourself. A half-ton pickup carries about 1,500 pounds safely.
| Material | Per cubic yard | Half-ton pickup |
|---|---|---|
| Bark or hardwood mulch, dry | 400 to 800 lb | 2 yards |
| Compost | 800 to 1,200 lb | 1.5 yards |
| Topsoil | 2,000 to 2,400 lb | Two-thirds of a yard |
| Gravel, crushed stone, sand | 2,500 to 2,900 lb | Half a yard |
Which mulch
- Shredded hardwood: the default. Knits together on slopes, lasts a season or two, cheap in bulk.
- Pine bark nuggets: slower to break down, float away in heavy rain, good on flat beds.
- Cedar or cypress: longer lasting, some insect resistance, costs more.
- Dyed mulch: holds colour for a season; check it is made from clean wood, not pallets.
- Pine straw: light, cheap in the South, needs topping up twice a year.
- Stone: permanent, no breakdown, but heats the soil and is hard to change later.
A spring refresh in one morning
- The week before: measure every bed, run the calculator, order bulk delivery for Saturday morning. Ask the driver to dump on the driveway on a tarp.
- Friday evening: pull weeds, cut back dead growth, re-cut the bed edges with a flat spade. Edging is what makes new mulch look professional.
- Saturday, first hour: rake the old mulch flat, fluff it, and remove any matted layer that sheds water.
- Then: wheelbarrow loads from the pile, dump in small heaps across each bed, spread with a rake to 2 to 3 inches. Pull it back from stems and trunks.
- Last: water the beds lightly to settle the mulch and sweep the drive.
Two people with a wheelbarrow move about one yard every 30 to 40 minutes. A four-yard job is a morning.
When to call a landscaper
At five yards and up, a landscaper with a dump trailer and a crew of two does the delivery, spreading and edging in a couple of hours, often with the material at their trade price. For sloped yards, big beds or anything you cannot get a wheelbarrow to, it is money well spent.
Find landscapers near you
Compare local landscaping companies on ProBusiness101. Listings show services, photos of finished beds and direct contact details.
Browse landscapers