Mulches for Home Grounds: Depths of Mulches

Except where weed-barrier fabrics are used alone or in combination with chips, stones or other material, apply most mulches to a depth of 3 to 4 inches. Apply straw, dried leaves and similar materials to a depth of 4 to 6 inches.

Some mulches, particularly straw and loose leaves, may harbor rodents so do not place them closer than 6 inches to the base of woody plants. When these types of mulches are placed next to the plant, rodents living in the mulch may chew the bark of the plants, girdling and eventually killing them. Mulches in contact with bark of woody plants may keep it too moist.