City of College Park, Maryland

Public Works

Compost vs. Wood Mulch: Which One and How Much do I Need?

SMARTLEAF® Compost & Wood Mulch
Prices, Pickup, and Delivery Options
How SMARTLEAF® Compost and Wood Mulch are Made

Compost has more soil-like qualities and is best used by mixing into your existing soil or planting beds. It is also great to use as a top dressing for lawn and grass seeding projects. Compost is different than soil, top soil, or dirt, however, in that it is only organic matter. Soil is composed of broken rock (sand, clay, silt) and organic matter. Compost is not a substitute for fill dirt! Compost will continue to break down. Compost can be used to replace or enhance the organic component of soil.

Wood mulch is best used as the final (top) layer in planting beds or around trees. It should be spread around your plants, shrubs, and trees to help conserve soil moisture and inhibit weed growth. It has not been screened or composted - it is made of ground raw wood.

Compost and wood mulch are often used in conjunction: compost is added as a soil amendment and wood mulch is then placed on top of the soil, around plants.

How Much

To estimate the amount of material you will need, follow this calculation:

  • Multiply the length × width × depth (all in ft.) of the area you are covering. This gives you the cubic feet of material you need.
  • Divide the cubic feet by 27 to get the cubic yards of material you need (there are 27 cubic feet in a cubic yard).

Example: if you are covering an area 8 ft. by 10 ft. and want it 6 inches deep:

  • 8 ft. × 10 ft. × 0.5 ft. = 40 cubic ft.
  • 40 cubic ft ÷ 27 = 1.48 cubic yards (approximately 1.5 cubic yards)

You can also use this handy calculator - click here - just put in your measurements and it will give you quantity needed.

Conversion Tid Bits

  • 1 Cubic Yard = 27 Cubic Feet
  • 3 Feet = 1 Yard
  • 144 Square Inches = 1 Square Foot
  • 9 Square Feet = 1 Square Yard


  • A truck with a 4 foot bed can hold 1/2 cubic yard
  • A truck with a 6 foot bed can hold 1 cubic yard
  • A truck with an 8 foot bed can hold 2 cubic yards
  • 1 Cubic yard will cover 162 square feet if spread 2 inches thick.
    1 Cubic yard will cover 108 square feet if spread 3 inches thick.
    1 Cubic yard will cover 81 square feet if spread 4 inches thick.
    1 Cubic yard will pot 200 - one gallon pots.
    1 Cubic yard will pot 40 - five gallon pots.
  • A 1/2 cubic yard is 20 five-gallon buckets
  • A 1/4 cubic yard is approximately any of the following:
    - 10 five-gallon buckets
    - 3 paper lawn bags half filled
    - A 3 feet x 3 feet area if spread 12" thick