University of Minnesota
University Relations

Unit's home page.

Seasonal care for trees & shrubs: Mulching


Mulching with organic mulches (e.g. leaves, needles, hardwood and softwood bark and wood, grass, cocoa hulls, straw, etc.) helps to maintain tree health by aiding in water retention, inhibiting weed development, protecting from lawn mowing equipment, offering a layer of insulation during cold weather and adding organic matter into the soil (Carlson, 2003). At planting or transplanting time add a mulch layer 2-4″ deep around the tree as wide as you can tolerate but, to avoid stem damage, not against the trunk.  Mature trees can be mulched at any time.

Over time this mulch will break down and decompose; therefore it is important to make the necessary additions each year. Before making any additions, lightly and thoroughly rake existing mulch to break up compacted or crusted layers (Carlson, 2003b).  Mulching may act as an alternative to fertilization if coarse wood chips or leaves are used (Hagen, 2003).

For more information : Tree mulching booklet (.pdf) and Mulch in managed landscapes (.pdf)

More information on each step:

Authored by Rebecca Koetter, Gary R. Johnson, and Dave Hanson: University of Minnesota
Funded in part by USDA Forest Service: Northeastern Area
Chart designed by Andrew Rose:

Download & print your own poster or magnet copy of the “Seasonal Care for Trees and Shrubs in Northern U.S. Climates”

Tags: , , , , , , , , , , , , , , , , , , , , , , , , , , ,

3 Responses to “Seasonal care for trees & shrubs: Mulching”

  1. […] Mechanical damage (e.g. lawn mower or weed whip abrasion) can be avoided when a mulch ring (see mulch) or a plastic guard is in place. The plastic guard should only encase the portion of the lower stem […]

  2. […] Care for Tr… on Seasonal care for trees & …Seasonal Care for Tr… on Seasonal care for trees & …Seasonal Care for Tr… on Seasonal care of trees & s…Seasonal Care for Tr… […]


Follow sitewide updates:


Email Newsletter icon, E-mail Newsletter icon, Email List icon, E-mail List icon Sign up for our Email Newsletter


Rebecca Koetter