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Using Mulch

The Bay-Friendly Landscape Guidelines recommend protecting all planting areas with a minimum of 3 inches of mulch. 

California's Water Efficient Landscape Ordinance (WELO) now requires the use of compost and mulch on permitted landscapes. Find out more

Mulch Best Practices

  • Specify the finished grade to accommodate a 3-inch layer of mulch.
  • Chip trees that will be removed from the site and use the chips on site as mulch.
  • Use local recycled mulch produced from green waste.
  • Keep root crowns free of mulch.
  • Do not use landscape fabric under mulch.
  • Use medium or light color mulch to avoid heat island effect.
  • Specify a 3-inch layer of mulch wherever mulch depths are mentioned in construction documents.
  • If sheet mulching is specified, include a sheet mulching detail in planting plans. See model sheet mulching specifications in Bay-Friendly Landscaping Guide to Mulch.
  • Include notes on clearing and demolition plans and specifications if onsite trees are to be chipped for mulch.
  • Integrate these practices into a soil management plan.

Calculating Mulch Quantities

Spread a 3-inch minimum layer of coarse mulch over the surface of all non-turf planting areas. Areas that will be planted with groundcover should also be spread with 3 inches of mulch. If the site is large, it’s good practice to keep a few small areas free of mulch to provide habitat for native bees.

To determine how much mulch you need, use our online mulch calculator or use this formula:

Total cubic yards of mulch = (A/27) x (B/12)

A = Total planting area in square feet to cover with mulch

B = Total inches of mulch required

1 cubic yard = 3 ft x 3 ft x 3 ft = 27 cubic feet

1 foot = 12 inches

Mulch Resources