Mulch Calculator
Calculate exactly how much mulch you need for garden beds, tree rings and landscaping areas. Enter the dimensions and depth — our mulch calculator instantly shows cubic yards, cubic feet and the number of standard 2 cubic foot bags required.
How to Use This Calculator
- Choose Imperial (ft/in) or Metric (m/cm).
- Enter the length and width of the bed or area.
- Enter the desired depth — 2–3 inches is typical.
- Get instant results showing cubic feet, cubic yards and bags.
Mulch Volume Formula
Cubic Yards = Volume (ft³) ÷ 27
Bags (2 cu ft) = Volume (ft³) ÷ 2
Mulching Tips
- Apply mulch in spring after soil has warmed, or in autumn before winter frosts.
- Remove old mulch if it is matted or mouldy before applying a fresh layer.
- Keep mulch away from direct contact with plant stems to prevent disease.
- Bulk mulch (by the cubic yard) is significantly cheaper than bagged for larger areas.
- Rake the surface of old mulch to break up any crust before adding a thin top-up layer.
Frequently Asked Questions
How much mulch do I need for my garden beds? +
A 2–3 inch layer of mulch is ideal for most garden beds. For a 100 sq ft bed at 3 inches deep, you need about 0.93 cubic yards. Enter your bed dimensions into our calculator for an exact figure.
How deep should mulch be applied? +
Apply 2–3 inches for most plants. Deeper than 4 inches can prevent water and air from reaching roots and may cause rot. Keep mulch 2–3 inches away from plant stems and tree trunks.
How many bags of mulch do I need? +
Standard bags are 2 cubic feet. To cover 100 sq ft at 3 inches deep, you need about 12.5 bags (round up to 13). Our calculator shows the exact bag count for your area.
How much does a cubic yard of mulch cover? +
At 2 inches deep, 1 cubic yard covers 162 sq ft. At 3 inches, it covers 108 sq ft. At 4 inches, it covers 81 sq ft.
What type of mulch is best for garden beds? +
Shredded hardwood or bark mulch works well for most garden beds — it breaks down slowly and improves soil. Pine straw is good for acid-loving plants. Avoid dyed mulch near vegetables.