How to Use Mulch Calculator

Enter the depth in Inches. Enter width in feet or inches. Enter length in feet or inches

The cubic yards required will be calculated

Mulch Calculator


How To calculate how much Mulch is needed

This calculator can calculate the amount of mulch you need for a rectangle area, triangular area and a round/circular area.

Example 1: Rectangle Area
  • Measure the length of the area, the length is 6.
  • Then we measure the width, which is 4 feet and the depth is: 3 inches.
  • We then get the area of the rectangle Length X Width: 6 X 4 = 24
  • We divide the depth by 12 to convert inches to feet
  • Now we have to get the volume of the area with = Depth X Area: (3/12) X 24 = 6
  • Now we divide the volume by 27: 6/27 = 0.22 cubic yards are needed of pea gravel
Example 2: Triangle Area
  • We measure the depth:4 inches
  • After measuring the depth, measure the length of the triangle, each side of the triangle is equal at 3 feet.
  • We calculate the area with 1/4 X Square root[(3+3+3) X (3+3-3)X(3+3-3)X(3+3-3)] = 3.89
  • Now we multiply the area by depth: 3.89 X (4/12) = 1.296
  • Once more divide the depth by 12 since its in inches
  • We than divide the volume by 27: 1.296/27 = 0.048 cubic yards of pea gravel
Example 3: Circle Area
  • Measure the depth at 3 inches
  • Then the width is measured at 4 feet
  • We calculate the area PI(3.14) X (width/2): 3.14 X `(4/2)^2` = 12.56
  • We then multiply the area by depth to get the volume: 12.56 X 3/12 = 3.14
  • Once again divide the depth by 12: 3/12 in the above equation
  • Now we get the cubic yards: 3.14/27 = 0.116
  • 0.116 cubic yards are needed

What is mulch? Mulch can be any material spread on top of soil in planting beds as a covering. Generally the material used is organic; it can also be more permanent mulch such as plastic (polyethylene) sheeting.

There are many benefits to using mulch, similar to pea gravel. Technically any organic material can be used as mulch for ground cover.

Mulch is often said to improve the appearance of the garden/landscape. The material helps retain moisture levels in the soil to lessen irrigation/watering needed and acts as insulation to protect the roots from extreme heat or cold. It also effectively suppresses common garden weeds. Mulching also helps extend your growing season by allowing you to move your planting date earlier, wield earlier harvests and grow crops longer into the season.

A benefit of using organic mulch is that it decomposes over time which supplies the surrounding soil with fertilization and nutrients. Depending on your mulch material, the decomposition of certain mulches can either add acidic levels to your soil (Pine Straw Mulch) or make it neutral/sweet (Alkaline) using Hardwood Bark Mulch. While more expensive, it is best for amending your soil.

An inexpensive common option is using old hay; taking care to build up to a depth of 30cm approximately to prevent the grain’s own seeds from sprouting weeds. For general flower beds, simple bark mulch suffices, spreading them across the bed up to 10-15cm. The flip side is that the mulch will need to be replaced. Ideally gardens should be mulched twice a year – once in spring and once in the fall.

Pea gravel here has an advantage in that it does not need to be replaced as often. Calculationworld also has a Pea Gravel Calculator. Plastic sheeting or Plastic mulch can also be more durable and has been used in commercial vegetable production for over 50 years. With technology, many options become available.

Clear vinyl sheets aids in solarization, ridding the soil of unwelcomed pathogens, insects and diseases in a non-chemical, organic and affordable way. Whereas Black Plastic mulch is great for vegetable crops that love heat (tomatoes, strawberries, pumpkins, and melons).

White Plastic Mulch acts as a cooling agent to allow plantation of cooler weather corps in warmer climates (cauliflower, cabbage, peas, and broccoli).With innovation, Infrared Transmitting (IRT) mulch have combined the ability of weed control like Black plastic mulch, while still pigmented to reduce the transmission of light to discourage weeds which can be an issue with Clear plastic mulch. A wide variety of other colored mulches, including red, yellow, green, blue, and silver are available, each with a differing effect on radiation levels in the crop canopy and light reflection.

Common materials used as mulch

  • Grass clippings
  • Wood chips
  • Cocoa hulls
  • Hay
  • Crushed seashells
  • Pine needles
  • Leaves
  • Stone
  • Straw
  • Bark
  • Sawdust
  • Shredded bark
  • Cardboard