Mulch Calculator: One Yard, Thirteen and a Half Bags
Enter your project dimensions
The decision most people are really making in April is not how much, it is how. A cubic yard holds 27 cubic feet, and a garden center bag holds two, so one bulk yard and thirteen and a half bags are the same quantity of shredded hardwood arriving two entirely different ways. The mulch calculator gives you both numbers off one set of bed measurements, which turns a guess into a comparison you can make before the car is loaded.
Am I mulching the whole bed, or only the part that shows?
The whole bed, including the ground under the shrubs. Plants sit in it rather than on it, and a layer that stops at the leaf line leaves bare soil exactly where weed seed lands.
Foundation borders curve, so run the tape along the middle of the curve rather than the outer edge and treat the bed as a long rectangle at its average width. Pace the width at three or four points and use the middle figure. Island beds and anything roughly round go in on the circle setting, which asks for the diameter straight across. The multiple-areas option takes up to five, which covers most suburban yards in one run; anything beyond five is two runs added together.
For a worked example, take a foundation border 38 feet long that averages 4.5 feet deep. That is 171 square feet.
Last year's layer is still there. Do I still enter 3 inches?
No. Two is the number over an existing layer, and three belongs on bare soil. Depth is the single entry that moves the answer most, so it is worth getting right per bed rather than per garden. The box takes one figure for a whole run, though, so beds at two inches and beds at three are two runs added together.
| The bed in front of you | Depth to enter | Why that figure |
|---|---|---|
| Last year's mulch, still loose | 2 inches after raking the old layer open | Tops the color back up without burying the crowns |
| Bare soil in a new bed | 3 inches | Enough to shade weed seed and hold moisture through a humid July |
| Anywhere at all | 4 inches is the ceiling | A deep layer that stays wet cuts air off from the roots |
| Beside the house wall | 2 to 3 inches, held 6 inches back from siding | Keeps a damp layer off the foundation line |
| Around a trunk | 3 inches, pulled 3 to 6 inches clear of the bark | A level donut, never a cone against the tree |
Depth is entered in inches and the form will accept anything from 0.25 up to 24. Mulch lives at the bottom of that range, and the number that matters is the 4-inch ceiling rather than the 24-inch one.
Carrying the example on: the 38 foot border is a refresh, so 2 inches goes in. Two inches is 0.1667 of a foot, so 171 square feet gives 28.5 cubic feet, which is 1.06 cubic yards, or about 14 bags. A new island bed 9 by 12 feet is 108 square feet on bare ground at 3 inches, and 108 times 0.25 comes to exactly 27 cubic feet, which is one cubic yard on the nose, or 13.5 bags. Both beds are invented for this page. Together they take a shade over 2 cubic yards.
Why is the ton figure almost nothing on a full yard?
Because this is the lightest thing in the catalogue by a distance. Shredded hardwood is published here at roughly 600 lb per cubic yard, which is 0.30 tons, and that figure is approximate.
Put it next to the other materials that go into the same garden and the gap is the point. A yard of screened topsoil runs about 2,200 lb, a yard of pea gravel about 2,800. The same volume of mulch is roughly a quarter of either. That is why it is sold and delivered by volume rather than by weight, why space rather than weight decides the load, and why the tonnage on your result screen is the least useful of the three figures it gives you.
Volume is also why the calculation does not change between mulch types. Shredded hardwood is what the tool is set for, and its fibers interlock well enough to stay put on a mild slope. Chips and nuggets may last a season or two longer but can float off in the kind of downpour a summer thunderstorm or a tropical storm brings through here. Dyed material holds its color longer. Whichever you pick, the yardage is identical; only the look and the refresh interval move.
Do I need the 5 percent box for something I am raking out by hand?
Not really, and this is the one page where unticking it is reasonable. The box adds 5 percent for compaction and spillage, which earns its place on stone that gets rolled. Mulch is spread loose and settles on its own over a season.
What is worth building in instead is the bed edge. Borders always take more than the plan suggests, so round the total up to the next half yard rather than relying on a box. On the two example beds above, 2.06 cubic yards is a 2.5 yard order, and the surplus goes on the bed behind the garage that never gets measured.
Bulk by the yard, or bags in the back of the car?
Run the numbers and the trade is visible. The result screen gives cubic yards for a bulk drop alongside the bag equivalent at 13.5 per yard, so the comparison is right there on the same line.
- Bagged means no pile on the drive and no tarp, and as many car journeys as the bag count comes to.
- Bulk Shredded Mulch by the yard arrives in one drop, and the cubic yard figure is what you order in.
- For a playground fall zone, neither: that wants at least 6 inches of playground-certified chips, which is a different product from landscape mulch.
If beds and a bed rebuild are happening in the same week, remember that mulch is the top layer only. Ground being rebuilt underneath wants Garden Soil, sized on the soil calculator, and mulch goes over the finished surface.
What happens to the pile if I do not spread it this weekend?
It gets worse quickly, and it is in the way the whole time. Three yards takes up roughly the footprint of a small car, so leave a parking space clear and put a tarp down before the truck tips, because shredded material marks fresh concrete. Aim to have it spread inside a week or two; a big pile left a month heats up and turns sour. Budget something like 30 to 45 minutes a yard with a wheelbarrow.
Set the yardage and a date on the product listing. Delivery is arranged at checkout by ZIP code, and the delivery page covers what the truck needs to reach the drop spot.
Common questions
How close does the estimate get on beds that curve all over the place?
Close enough to order from, as long as the width is averaged honestly. Running the tape along the outside of a curve is the usual error and it overstates the area, sometimes by a tenth. Take the width at several points, use the middle value, and treat any bed narrower than about two feet as the width it actually plants out at rather than the width you would like it to be.
I have my cubic yards. Where do I put that number?
On the Shredded Mulch listing, which is sold by the cubic yard, so the yardage from the result goes straight into the quantity box along with your delivery date. The bag figure beside it is only there for comparison; it is not an ordering unit on this site.
Where should the driver tip it if the beds are all out the back?
On a hard surface near the gate, with a tarp under it and headroom clear of the tipping body. Mulch on grass will scorch a rectangle into the lawn within days, and a pile at the wrong end of the property turns a two hour job into an afternoon. Walk the wheelbarrow route first and check the gate width, since a loaded wheelbarrow is wider than an empty one.
The result shows tons next to the yards. Should I be reading it?
Only for the truck's sake. Yards is what you order, and what the listing is sold in. The tonnage is small enough on this material to be misleading if you use it for planning, since 2 yards is roughly 1,200 lb. It is worth a glance if you are combining mulch with something heavy on the same delivery, and otherwise it can be ignored.
Is the depth I enter the fluffed-up depth or the settled one?
Enter the depth you want it to look like the day you spread it, loose and raked level. It will settle and it will break down, which is why beds get topped back up each year rather than built deeper. Where last season's layer is still 2 inches thick and matted, loosen it with a rake and take the total to 2 or 3 inches rather than adding a fresh 3 on top of it.
Related calculators
Skip the 27-bag cart.
Bulk shredded hardwood by the yard, tipped in your driveway, delivery free.
