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Recognize the difference between compost and mulch – How to choose the right remedy for your garden soil.

Although both benefit garden plants, the difference compost mulch in a combination can have a negative impact on plant growth. In fact, these terms often occur as synonyms in gardening. This causes many amateur gardeners to think they are simply two different words for the same thing. Even experienced gardeners often use one word when they actually mean the other. Here is some useful information that should provide more clarity on the meaning and use of these essential gardening tools.

Why the difference compost mulch is important for garden maintenance

in garden beds recognize the difference compost mulch for the purpose of soil care and use it correctly

There are some factors that could complicate the use of the two sources of nutrients in the garden. This is the fact that compost is suitable as a mulch, while mulch can have similar effects on the garden soil. In addition, it’s not surprising that many people can’t tell the difference between the stuff and use it properly. So if you want to better understand the difference, you should first find out what makes them different. This will help you optimize soil care in your garden.

What characterizes compost

natural fertilizer and difference compost mulch in terms of garden maintenance

As an organic soil amendment, compost actually looks and feels like soil. You can buy the soil nutrient at your local garden store or purchase it from a commercial composting facility. The stuff can also be made in a compost bin, such as a bokashi bucket, or in your backyard as a compost pile. In some areas, residents can even get free compost for their home gardens through community programs.

composting kitchen waste with earthworms in a compost pile

In addition, compost is the result of microorganisms decomposing organic matter such as kitchen scraps, chicken or animal manure, leaves, organic garden waste and some paper products through the process of aerobic biodegradation. For example, if you have a compost bin, you can add banana peels, used coffee grounds, unbleached paper coffee filters, twigs, leaves and lawn clippings . In such a controlled environment, these products will decompose and become nutrient-rich compost that you can use in your garden.

After composting has taken place

recognize the difference compost mulch and optimize soil care in the garden


How long compost takes to decompose depends not only on the material, but on many other factors. Decomposition can take anywhere from two weeks to two years. The right balance of green and brown in a compost pile is quite important. In addition, the right amount of moisture, aeration, turning the pile, its size, ambient temperature, and the presence of worms and microorganisms that break down the compost all play a crucial role.

as a hobby gardener know more about the difference compost mulch and improve plant care

Once the compost is fully decomposed, it becomes organic material or humus. After composting, none of the original materials are recognizable. In addition, mature compost is dark brown and crumbly, with earth-like particles, and the mass is characterized by an earthy smell.

What you can use compost in the garden

use a rake to spread mulch on the soil in the garden as a ground cover


You can mix the natural nutrient into your garden soil to improve soil structure and add nutrients accordingly. In addition, compost is an ultimate form of natural recycling. However, since the nutrient composition of compost depends on the original materials, just adding it to a garden soil as a fertilizer is not enough. Especially if the soil is depleted by crops each year, such as in a vegetable garden. It is also necessary to selectively apply nutrients in the form of fertilizer.

gardening in autumn mulch the soil with lawn clippings and prepare for winter

The other important function of compost is soil improvement for optimal soil health. Organic matter such as mature compost loosens the dense texture of heavy clay soils, allowing plants to grow more easily. The amendment also improves soils at the other end of the spectrum, such as sandy soils, because organic matter holds water and nutrients better, so sand doesn’t wash out as quickly. In some cases, especially with coarser compost that looks more like mulch, it is used as a mulch to cover garden beds. However, this is a bit misleading, as compost is a soil amendment, but not the same as fertilizer.

What recycled materials is mulch made of?

colored mulch from bark for visual improvement of garden soil

Mulch can include both inorganic and organic materials that can be spread on the soil as a blanket. For example, the material used can be leaves, lawn clippings, bark, straw, recycled rubber, gravel, crushed shells, nut shells or similar products. While you can use a ground cover of gravel as mulch, it is far more common to use the term for organic materials. The most popular forms of mulch are wood chips or shavings, hardwood and softwood bark. Other mulches include pine needles, pine cones, hay, straw, cocoa, rice, buckwheat hulls, other crop residues, tree leaves, and grass clippings.

different materials like gravel and rubber for the production of mulch

Gravel, rubber mulch and similar inorganic products that technically fall under the term mulch offer some of the benefits found in all mulches. These include limiting the growth of weeds, moderating soil temperature, reducing erosion, and retaining moisture in the underlying soil. However, when using organic mulches, such as leaves, bark, wood chips or lawn clippings, gardeners also reap the added benefits of improved soil structure and additional nutrients as they decompose.

How mulch helps the garden soil

bark as mulch needs longer time to decompose in the garden soil

Mulch is primarily used to cover the soil of garden beds and around garden plants. Thus, you accomplish three things: retain moisture, control weeds and improve visual appearance. In addition, mulch helps the garden soil retain moisture so it doesn’t dry out as quickly. The effectiveness of mulch against weeds depends on the type of mulch – the thicker and denser the mulch, the harder it is for weeds to grow. Finally, a mulched flower bed looks neater than one with bare soil, but that depends on preference.

How the difference compost mulch affects soil care

take care of garden plants and apply a straw cover against weeds

Because the uses for compost and mulch are different – soil fertilization and amendment vs. ground cover – it’s usually not a good idea to use them interchangeably. When mulches of organic materials break down, they eventually enrich the soil with organic matter and nutrients, but there is a caveat. Bark mulch and other woody materials take a long time to decompose. Grass clippings and other fresh plant material, on the other hand, decompose faster, but the microorganisms in the soil need nitrogen to do their decomposition work. During this time, they tear it away from any nearby plants. This can stress the plants and lead to chlorosis. This is also why it is not recommended to add compost to the soil until it has fully decomposed.

load lawn clippings in a garden cart and use as mulch for the garden soil

While lawn clippings should not be left to rot on top of garden soil, sometimes returning them to the lawn to decompose is actually recommended. Mowing the lawn scatters grass clippings over a large area, and it’s nowhere near as dense as piling. Using other organic materials that have not fully decomposed as mulch can be equally problematic. For example, if you pile a thick layer of whole leaves without first shredding them, you prevent air and water from getting into the soil. Accordingly, the moisture buildup can also lead to fungal diseases and cause root rot in nearby plants.

When to use compost and when to use mulch

apply mulch made of organic materials around garden plants as protection

Now that you understand the difference between compost and mulch, the next logical question is: Which is better for my garden – compost or mulch? If your goal is to increase food crop production, get more blooms on your flowers, or encourage your plants to grow faster, you can use compost. However, if limiting weed growth, controlling erosion and conserving soil moisture are your goals, mulch is a better choice. Most gardeners want all of these things to happen in their gardens at the same time. Therefore, it is common and often best to use both compost and mulch.

hobby gardener mulches small fir tree in a pot in the garden

So the choice between compost or mulch depends on the purpose. If your primary purpose is to enrich the soil to add nutrients and improve its texture, you should work mature compost into the top few inches of your garden soil. If your primary concern is to keep the weeds down and reduce watering, apply mulch. Preferably, this should decompose over time so you get the added benefit of improving your soil. Ideally, do both – recycle as much of your garden waste and kitchen scraps as possible and mulch your garden beds with it.