Spring mulch season: how much mulch do I need and how do I haul it?

Key takeaways

• Cubic yards = square feet × depth in inches ÷ 324.
• One yard covers about 324 sq ft at 1 inch, 162 at 2 inches and 108 at 3 inches.
• One cubic yard equals 13.5 two-cubic-foot bags.
• Howard County sells HoCoGro mulch at Alpha Ridge for $21 a cubic yard, tax included.
• A level 6x12 load of mulch weighs about 3,550 lb, and with the trailer about 6,650 lb, more than a half-ton can tow.

How do I calculate how much mulch I need?

Measure each bed's square footage, multiply by the depth in inches, and divide by 324.

A cubic yard is 27 cubic feet, and 324 is 27 × 12, so this formula turns inches straight into yards. Measure odd-shaped beds as rectangles and round up. For a ring around a tree, use 3.14 × radius² and subtract the trunk area. Add up every bed, including the narrow strips along walks and foundations. They add up fast.

Example: 600 square feet of beds at 3 inches is 600 × 3 ÷ 324 = 5.6 cubic yards, or about 75 two-cubic-foot bags. Order 6 yards.

How deep should mulch be?

One to three inches, kept an inch or two away from tree trunks.

University of Maryland Extension's guidance is that 1–3 inches is all you need, and that mulch piled against trunks ("mulch volcanoes") harms trees. One case it describes had 17 inches of mulch around a tree that died. Leave a gap of about 1–2 inches around each trunk.

If last year's mulch is still there, measure it before you order. A bed with 2 inches left needs only a 1-inch top-up, which is a third of the mulch. Refreshing color only? A 1-inch top-up uses a third of the mulch a new 3-inch bed needs. Mulch season here runs March through May, and suppliers and yards are busiest on spring Saturdays, so plan ahead.

Is bulk mulch cheaper than bags?

Usually, once you need more than a couple of yards. One bulk yard replaces 13.5 two-cubic-foot bags.

In Howard County, the county sells its own HoCoGro products at the Alpha Ridge Landfill's Wood Waste Area, 2350 Marriottsville Rd. Prices include sales tax, and it's credit card only:

To compare, multiply your bag price by 13.5 for each yard. Since May 1, 2026, Alpha Ridge adds a 2.45% fee to card transactions. Wood Waste Area hours are Monday–Saturday, 8am–4pm for residents and 8am–3:30pm for commercial customers. Call 410-313-6444 to check loading before you go. Landfill fees, hours and rules are set by each county or site and can change without notice. We don't control them; call the site before you go.

How much mulch fits in a 6x12 or 7x14?

The bed size, not the weight, is the limit. A 6x12 holds about 4.4 yards level and a 7x14 about 7.2.

Mulch weighs roughly 800 lb per cubic yard, so a level load is well under either trailer's payload.

Wet mulch weighs more, so use the load calculator if you're mixing in compost or topsoil. The 6x12 rents for $119 a day ($126.14 with tax), which covers most mulch runs with time to spare.

Can my truck tow a trailer full of mulch?

Maybe not. A full 6x12 of mulch plus the trailer weighs about 6,650 lb.

The 6x12 weighs 3,100 lb empty. Add 4.4 yards of mulch at about 3,550 lb, and you're at roughly 6,650 lb. A 2026 F-150 is rated for 5,000 lb of trailer and 500 lb of tongue weight without weight distribution. With that truck, about 2 yards is the practical limit per trip (around 4,700 lb total). Run your truck in the tow checker before you book. Your vehicle's manufacturer ratings and manual always win.

How do I load and unload mulch without a mess?

Have the loader spread it across the bed, tarp it, and dump it where you'll use it.

• Ask the loader operator to spread the load over the axles, not drop it all at the rear.
• Keep the load level with the sides, then pull the tarp tight and latch it. Mulch blows.
• At home, lay a tarp on the driveway first, check for overhead wires, and dump onto it.
• Use the spreader gate to lay mulch in a strip along a long bed, with both chains set to the same length.
• Dump on your property, not the street. Howard County limits commercial vehicles on residential streets to 6 hours.

Planning a patio at the same time? Our patio hauling guide covers stone and pavers.

What about compost and topsoil?

Use the same formula, but expect much heavier loads. Weight, not the bed, limits topsoil.

For vegetable beds, University of Maryland Extension mentions an inch or two of compost. At 1 inch, a yard covers 324 square feet. At 2 inches, it covers 162. Topsoil runs about 2,100 lb per cubic yard, nearly three times as heavy as mulch:

Howard County's HoCoGro blended topsoil mixes soil with county compost and brings soil organic matter to 5–9%. If you're buying mulch and topsoil on the same run, keep the topsoil under the payload and don't top it off with mulch. They mix when you dump.

One tip that saves a trip: haul your spring brush and leaf cleanup to the same Wood Waste Area on the way, then load mulch on the way back. Bring the trailer empty to the loading area, and take your tarps home. The area is plastic-free.

Questions

Sources

• University of Maryland Extension (Maryland Grows): Mulch volcanoes kill trees
• University of Maine Extension: mulch coverage table and 27 cu ft per yard
• Howard County: Wood Waste Area (HoCoGro prices, hours)
• Howard County: HoCoGro info sheet (tax-included prices, credit card only)
• Howard County: HoCoGro page (2.45% card fee from May 1, 2026)