Mulch: bags or bulk?

A cubic yard of mulch is thirteen and a half two-cubic-foot bags. That one figure settles most of this decision before any price is quoted — and the rest of it is settled by a minimum load you pay for whether you spread it or not.

The pack sizes, and what they come to

Bagged mulch comes in 2 ft³ and 3 ft³ bags. A cubic yard is 27 cubic feet, so that is 13.5 of the small bags or 9 of the large — before any allowance. The mulch calculator adds the settling allowance below and gives both counts for any bed.

Three beds at a 3 in depth, from the mulch calculator
BedVolume 2 ft³ bags3 ft³ bags
A 10 × 12 ft border 1.11 yd³ 15 10
A 20 × 25 ft bed 4.63 yd³ 63 42
A 40 × 30 ft front garden 11.11 yd³ 150 100

Why the calculator orders more than the bed holds

Mulch settles. Spread three inches and you get less than three inches of mulch after a fortnight and a rain, which matters because depth is the entire point — mulch works by keeping light off soil, and a layer that has settled below about two inches has stopped doing that.

So the calculator carries a settling allowance of 0% on top of the spread volume, and the counts above already include it. This is the one place a mulch order should be generous: the failure mode of buying too little is not a second trip, it is a bed that grows weeds all summer.

What bulk actually costs

Bulk mulch is not priced by the yard alone, and the yard price is the least interesting number in the quote. A yard sold loose comes with:

  • A minimum load. Most yards will not send a truck for less than two or three cubic yards. You pay for the minimum whether your bed takes it or not.
  • A delivery charge. Fixed, so it is brutal on a small order and rounds to nothing on a large one.
  • A pile on the drive. Which is a barrow job, and a deadline — a loose pile in the rain is heavier every day you leave it.

The mulch calculator takes all three. Enter a bulk price, a minimum load and a delivery charge and it reports the delivered total, the yards you are paying for and cannot use, and the real per-yard rate rather than the quoted one — which is usually the number that changes somebody's mind.

The rule of thumb, and where it breaks

Under about a yard, bags win on nearly any pricing, because you are not paying a delivery charge to move a wheelbarrow's worth. Over about three yards, bulk wins on nearly any pricing, because the fixed charges have been spread thin and bags have become a hundred and fifty separate objects to open, empty and dispose of.

Between those, it is genuinely close and it depends on your two prices. That is exactly the band the calculator is for.

The same argument, other materials

Topsoil and gravel behave identically — same minimum load, same delivery charge, same crossover — and the topsoil calculator and gravel driveway calculator both report the delivered cost the same way. For a raised bed, the raised bed soil calculator handles the mixes, which are the one case where the bagged product is not the same product as the bulk one.

And if the bed is not a plain rectangle, measure it in the square footage calculator first — it will hand the area straight across.