Why Use Mulch
- It suppresses weeds and makes weeds that do sprout easier to pull.
- It slows water evaporation from soil, so you don’t have to water as often.
- It insulates soil against temperature extremes. This protects shallow-rooted plants in cold regions and coddles crops as summer sizzles.
- It prevents soil compaction during downpours. Loose, uncompacted soil yields happy, healthy plant roots.
- It slows storm water runoff and helps reduce soil erosion. Less runoff means planting beds are absorbing more rain.
- It prevents disease organisms from splashing from soil to plant leaves, which reduces disease outbreaks.
- It gives planting beds a polished look, enhancing even the most basic landscape design.
Types of Mulch
- Organic materials include things like shredded bark, pine straw, compost or grass clippings. These materials break down over time, adding organic matter to soil and improving it.
- Inorganic mulches are more permanent and don’t readily degrade. Stone, weed fabric, rubber or geotextile mats are types of inorganic mulches.
How to Mulch
Apply a 2- to 3-inch-thick mulch layer. If you’re gardening in slow-draining soil, use a thinner layer (1 to 2 inches); for fast-draining soils like sand, aim for 4 inches. A too-thick layer can lead to plant rot, diseases, pests and rodents.
Extend mulch beyond the plant’s drip line — the point where the outermost edge of leaves occurs. To prevent rot, pull mulch back 2 to 4 inches from perennial crowns, shrub stems and tree trunks.
Water mulch after application. This keeps dry mulch from absorbing soil moisture (and stealing it from plant roots). Second, it helps anchor lightweight mulches easily carried by wind.
Julie A. Martens