Mulches provide many benefits for trees and shrubs: moderate soil temperatures, reduce soil moisture loss, reduce soil compaction, provide nutrients, improve soil structure, keep mowers and string trimmers away from the trunk. These benefits result in more root growth and healthier plants. When applying mulch, the following guidelines should be observed:
- The best mulch materials are wood chips, bark nuggets, composted leaves, or pine needles. Plastic, stone, sawdust, finely shredded bark, and grass clippings should be avoided. Do not use redwood or walnut mulch due to allelopathic effects.
- Mulch should be applied from the dripline to the trunk. If this is not practical, minimum mulch circle radii should be 3 feet for small trees, 8 feet for medium trees, and 12 feet for large trees.
- When applying mulch, it is not necessary to kill or remove existing ground cover. However, turf should be mowed very short and clippings removed prior to application. Mulch should be applied directly to the soil surface, do not use landscape fabric to separate the mulch from the soil.
- Mulch layer should be 2-4 inches thick depending on tree species and mulch.
- Mulch should not be placed against the trunk. Mulch will retain too much moisture against the trunk, potentially resulting in disease problems.
Original Article: https://www.ncufc.org//proper-mulching-for-trees.php
