What Is Mulch?
A mulch is any material, organic or inorganic, that is placed on top of the soil in a garden or landscape. . Mulching may cool or warm soil temperatures. It may control weeds.
Mulches are one of a gardener’s most valuable tools and an essential component of low-maintenance landscapes.
Ten Benefits of Using Mulch
1) Mulches help control weeds through prevention and slowing of weed seed germination.
2) Mulches regulate soil temperature by providing a layer of insulation over bare soil. How much regulation depends upon the type of mulches and in some cases, its thickness and color. The soil temperature may be either warmer or colder under mulch compared to bare soil.
3) Mulches assist in retention of soil moisture by reducing evaporation at the surface.
4) Mulches reduce soil erosion. A layer of mulch will lessen the impact and run-off of raindrops.
5) Mulches reduce the spread of disease by protecting above-ground plant parts from being splashed with fungal or bacterial inoculums from the soil. It also protects fruits from contacting the soil surface and in so doing, reduces the chance of rot.
6) Though generally in small amounts, most mulches will add some essential elements back into the soil.
7) Mulches improve soil tilth. As organic surface mulches decompose, they work down into the soil to increase air space, moisture retention and nutrient holding capacity.
8) Mulches reduce heaving of soils from frost. By loosening the soil structure, mulches lessen the tension between water molecules that form ice in the subsurface. Soil ice increases pressure which tears plant crowns and roots.
9) Mulches insulate against soil compaction. A cushion of organic materials on the soil surface will reduce the compaction of subsurface soil layers by absorbing the pressure due to traffic.
10) Mulches can improve the appearance of any planting site.
There are basically two types of mulches: organic and inorganic
An organic mulch is a mulch made of natural substances such as bark, wood chips, leaves, pine needles, or grass clippings. Organic mulches attract insects, slugs, cutworms and the birds that eat them. They decompose over time and need to be replaced after several years.
Inorganic mulches, such as gravel, pebbles, black plastic and landscape fabrics, do not attract pests, and they do not decompose.
TYPES OF MULCHES
SHREDDEDBARK Keeps soil cool and moist. Readily available. Goodweed control. Appropriate for ornamentals.
WOOD CHIPS Decorative, controls weeds
SAWDUST Inexpensive. Slow to decompose.
HAY Great winter insulator for bulbs, vegetables and perennials. Useful ingarden paths and around larger vegetables.
COCOA SHELLS Good for small plants, flowers, and vegetable gardens. Smells like chocolate
GRASS CLIPPINGS Great use for unwanted lawn clippings. Free and contains nutrients. Grass clippings make excellent mulch for the vegetable garden. A few layers will stop weed seed germination
LEAVES Good winter insulator. Contains a fair amount of plant nutrients. . Leaves are easy to obtain, attractive, and will improve the soil once decomposed
NEWSPAPER Excellent weed suppresser. No longer contains lead in the newsprint.
COMPOST Source of nutrients. Good for disease control.Improves soil and attracts earthworms.
STONE Low maintenance mulch. Decorative. Great for pathways.
PLASTIC Most useful in the vegetable garden. Warms soil. Excellent weed control
LANDSCAPE FABRICS (GEOTEXTILES) Excellent weed control in vegetable garden. Useful for soil stabilization. Specially designed matsfor use around trees
Using plastic mulch in the garden by Robin Mittenthal, March 2010
Soil and Mulch – Frequently Asked Questions (FAQ’s) – See more at: https://extension.umd.edu/learn/soil-and-mulch-frequently-asked-questions-faqs
Grass Clippings, Compost and Mulch: Frequently Asked Questions