Compost is an organic soil amendment that looks and feels like soil. It’s the result of microorganisms decomposing organic matter through the process of “aerobic biodegradation”. Mecklenburg County produces compost that we have “branded” as Queen City Compost ™ from leaves, ground up trees and organic yard waste.
We produce Queen City Compost by making “windrows” of the organic items listed above which “heats up” to around 150 degrees – that temperature is held for a prolonged period to kill off bugs, weed seeds and essentially “cures” the material. The windrow materials are screened after curing and then the compost is ready for use.
Compost should be mixed into the soil to improve soil structure and add nutrients. Because it is so rich and full of these nutrients, it is best tilled into soil for your plants to thrive and it should not be used alone.
As it continues to decompose in the soil, compost adds nutrients over time and continues to improve your garden soil. In garden beds where plants are already in place, compost is sometimes used to side-dress plants by spreading it around the plant and either allowing it to naturally work into the soil or using handheld gardening tools to lightly mix it into the soil without injuring existing root systems. Using compost has also been shown to substantially reduce watering. On lawns where compost has been mixed, significantly less watering is needed as the soil has a greater ability to retain water on its own.
Wood mulch is comprised of wood that is ground in large commercial grinders. Wood
mulch varies based upon what materials are ground up.
Wood mulch is typically used as the topmost portion of ground coverings for plants. It
can be used to refer to both inorganic and organic materials that are spread on top of soil as a top dressing. The material used could be leaves, lawn clippings, shredded wood.
Mulch provides benefits such as limiting weed growth, moderating soil temperature,
reducing the potential for erosion, and enhancing moisture retention in the underlying soil. It also adds visual appeal to your area.
When using organic mulch, such as shredded leaves, shredded wood or lawn clippings, gardeners get the added benefits of improved soil structure and added nutrients as it decomposes.
Okay, now that we have a basic understanding of what compost is and what mulch is, let’s make the differences a bit clearer.
Compost is mixed into the soil; whereas, mulch is spread on top of the soil.
Compost is best at adding nutrients to the soil and “improving” soil structure.
Mulch is best at limiting weed growth, preventing erosion and retaining soil moisture.
Compost is made up of decomposed, organic materials; whereas, mulch can be inorganic (think ornamental rocks or ground rubber chips) or organic materials like wood, that, in most cases, are not decomposed.
Compost is usually a rich dark color of deep brown to black, and no colorants are added. Mulch, however, can be dyed with various colorants in big machines to make it black, brown, golden or even red. Dying is more expensive and will cost more.