Organic Mulch Tips and Facts (exerts from Scott, 2007. J. Environ. Hort.)
- The benefits of maintaining a layer of organic-based mulch are great: improves soil moisture, reduces soil erosion and compaction, regulates soil temperatures, contributes to soil nutrition, improves plant establishment and growth, improves seed germination and seedling survival, increases overall plant growth performance, reduces weeds and disease, adds beauty, and saves money.
- A 1-inch layer of straw mulch can reduce evaporation by 35%, reduce water runoff by over 40%, and reduce soil erosion by 86%.
- Course mulches are more temperature moderating than fine-textured mulches, also thicker layers more than thinner layers.
- Not all mulches are created equal. Plastics, geotextiles, fine-textures organic mulches, sheet mulches, and mulches with waxy components created conditions that compact soils or create hydrophobic conditions, limiting soil infiltration and moisture. Organic-based mulches conserve water better than inorganic mulches and do not limit soil water infiltration.
- Mulching can proactively protect soils against compaction, but cannot reverse impacts.
- Root development and density is greatest under organic mulches as compared to plastic, bare soil, or living mulches.
- Gravel and stone mulches are generally not as effective as organic mulches in optimizing plant performance.