The Difference Between Compost and Mulch

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There can be several piles and layers of brown things in the garden and getting the terminology straight can be a little confusing. Two of the most common things found in garden landscaping are compost and mulch, so let’s break down the difference between them. This blog post will also briefly touch on the differences between mulch, soil, and dirt. 

Compost vs Mulch

What is compost? 

As we dig into the differences between compost and mulch, we must look at them individually.

Compost is organic matter that has been decomposed by microorganisms. Most commonly, compost is added to improve soil quality. You can throw in all sorts of organic waste around the house into your compost, from banana peels to grass clippings, whose nutrients (mainly carbon, nitrogen, phosphorus, and potassium) will supplement the soil. Composting gives you a great supplement to your garden soil while also decreasing your waste. 

There are a few things you shouldn’t compost, such as pet litter and dairy, as they can cause foul smells, attract pests, and promote disease. 

What is mulch?

Mulch is material, usually organic, that is used to cover the soil meant to serve as a protective layer. Notice how there is a layering difference between compost and mulch: the mulch goes on top of the compost which would normally be mixed into the soil.  

There are all sorts of benefits and uses to mulch. The most common are:

  • suppressing weed growth by shading the soil; 
  • controlling soil temperature (especially helpful for Chicagoland’s chilling winters); 
  • promoting the presence of earthworms. Their boring will help air filter through the soil;
  • limiting soil erosion by protecting your soil from surface running water;
  • retaining water by decreasing evaporation from soil. Using less water to maintain your plants can also help decrease your utility bills;
  • and enhancing the aesthetic–and therefore value–of your outdoor space. 

All sorts of materials can be used for mulch. Common choices are wood chips, dead leaves, pine needles, cocoa hulls, straw, shredded bark and stones. Sometimes, special gravel, plastics, and landscaping fabric are also used for inorganic mulch covers.

In short, the difference between compost and mulch is that compost is used to enhance soil quality while mulch is used to protect the soil itself. Mulch is one part of residential landscaping that Arbeen Landscaping specializes in. We also have most of the mulch types listed above available for our clients. Contact us today for the best landscaping professionals in Chicagoland. 

What is Composted Mulch?

The difference between compost and mulch gets a little blurry when we look at composted mulch, which is when you use your compost as mulch. Because mulch is defined as what goes on top of your soil, if what goes on top is a layer of compost, then it now counts as a mulch. 

Using compost as mulch is a practical choice when your compost pile is too large. By having a mulch layer made of compost, the nutrients will leach from the mulch layer into the soil, giving you a mulch with the additional benefit of soil supplements while also getting all the same benefits of having regular mulch. 

To really get the full benefits of mulch using compost, you would need a thick layer to produce the shade and protection. Two to four inches is a good layer to start with. Additional compost should be added to the mulch layer each month during summer and fall, and removed in the spring to let plants reach sunlight and grow. 

It should also be noted that while compost can function as mulch, mulch cannot function as compost. Mulch does not have the same decomposing bacteria as compost and does not provide the same nutritional support to soil, so it’s best to not mix in nut shells and wood chips into your soil. 

Soil vs. Mulch 

Soil is actually very complex. In simplest terms, it is the medium or material  in which plants grow. It is filled with organic minerals, as well as inorganic elements air, and water. Soil can also be divided into three main textures: clay, silt, and sand, most soils being a combination of all three.

What differentiates soil from mulch is that plant life actively grows in soil, while mulch is the material that goes on top of the soil for regulative and protective reasons. Mulch can help protect plants, but vegetation is not actively growing in the mulch itself. The two layers also stay separate. While compost can be mixed into soil, mulch sits on top as its own layer.

What about soil vs. compost?

Compost is often seen as too rich to function as a soil by itself. Instead, compost is usually mixed into the soil to enhance it. Adding compost to soil also does not change the texture of the soil, but it can alter soil composition by changing how much air and water the soil can contain or drain. Adding compost to soil also changes the balance of nutrients to what is best needed for your plants.

Then what’s dirt?

Dirt has multiple definitions, but what those definitions have in common is that dirt is a material of low value. It can be imagined as soil without any of the life-giving, nutritional properties. It’s the thing that gets in your nails and dirties your clothes. All in all, don’t worry too much about dirt. There are other types of earthy groundtops more important to landscaping and your outdoor space. 

Making the Most out of Mulch

If you’re looking to reap all the benefits of mulch while putting in none of the work, we at Arbeen Landscaping offer mulch services. We will help you choose which is the best mulch for your home or business landscape, then bring in fresh mulch and do all the back breaking work of hauling bags and distribution of mulch while you enjoy a fresh yard.