Mulch is primarily made from a variety of organic and inorganic materials, each serving different purposes in gardening and landscaping.
Organic Mulch Materials
Organic mulch is made from natural plant-based materials that decompose over time, enriching the soil. Common organic materials include:
- Wood chips and bark, often from pine or other trees, which break down slowly and improve soil structure
- Leaves and shredded leaves, which can be collected and chopped for mulch use
- Grass clippings, though they are often mixed with other materials to prevent matting and odor
- Pine needles (pine straw), which help suppress weeds and retain moisture without compacting
- Compost, which is fully decomposed organic matter used to add nutrients to soil
- Straw, hay, and other plant residues like shredded newspaper or cardboard
- Well-rotted animal manure, such as horse manure, which is nutrient-rich and moisture-retentive
These organic mulches not only protect and insulate the soil but also gradually add nutrients as they decompose
Inorganic Mulch Materials
Inorganic mulches do not decompose and thus do not contribute nutrients to the soil but can provide long-lasting weed suppression and aesthetic appeal:
- Small rocks, gravel, or crushed shells, which retain heat and can extend growing seasons in cooler climates
- Rubber mulch, made from recycled tires, used mainly in playgrounds and landscaping but offers no soil nutrients
- Plastic mulch sheets, used extensively in large-scale vegetable growing, though they pose environmental disposal challenges
Summary
Mulch can be made from:
- Organic sources: wood chips, bark, leaves, grass clippings, pine needles, compost, straw, manure, shredded paper.
- Inorganic sources: rocks, gravel, rubber, plastic sheeting.
Organic mulches improve soil health by decomposing and adding nutrients, while inorganic mulches primarily serve as durable ground covers
