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Does Compost Turn into Soil? What Is the Difference?

Once you have decided to grow your own food, the idea of exactly how to go about doing it becomes the next bridge that must be crossed and understanding all about compost and soil is the heart of that issue.  You need to understand a few basic concepts., such as the difference between compost and soil.

Compost turns into soil in less than a few months when hot composting and could take as long as a year or more when cold composting. Compost does eventually turn into soil, but it is essential to differentiate between compost, soil, and other elements that your food will be grown in.

Knowing the difference between compost and soil and how they work together and with other elements will help your organic growing experience be enjoyable and straightforward, leaving you with fantastic organic food and leaving a smaller carbon footprint on the world.

Compost vs. Soil: The Basics

Compost is a conglomeration of dirt and decaying materials that will eventually break down into rich soil perfect for growing organic foods. 

While compost will eventually become soil, soil is not compost.  Soil combines many things, some of which are not directly related to what we think of as “soil,” such as rocks and things of that nature.

To put it in fundamental terms, soil is the contents of the top layer of earth.  This is a primitive distinction between compost and soil.

How Long Does It Take Compost to Turn into Soil?

Compost is a manufactured substance that contains decaying materials mixed in with soil. Once those materials have been adequately broken down, then the compost does, in fact, become soil. 

Many factors determine the exact amount of time compost will take to break down and become soil.  One determining factor is whether you opt to make cold or hot compost.

Cold Composting

This is the easiest, most low-maintenance way of creating compost.  Generally, this is where you take out your leftover or rotted kitchen waste and toss it in a compost bin.  You do not have to churn the compost, and the process occurs quite naturally.

Cold composting can take quite some time to turn into soil.  It can take several months or over a year to complete the process. 

Hot Composting

If you are into a much more hands-on composting process, then hot composting could be the right option for you.  This option requires the compost to be turned over often, causing an internal heating process to speed up the breakdown of compost into soil.

In hot composting, compost can turn into soil in a matter of fewer than three months, making this a much faster option than cold composting.

Here’s an informative video explaining the differences between soil and compost, with more info below:

Can You Use Compost Instead of Soil?

It is possible to use compost rather than soil, though this is not ideal, and it causes the need for other materials to supplement the lack of topsoil.

It is suggested that you make the compost as fine as possible without pulverizing it to variable dust.  You should aim to make the compost as similar to the topsoil as possible.

You will also need to ensure that you mix the compost with a good fertilizer.  While compost is rich material, it lacks some minerals in topsoil, so the fertilizer will offer the compost the correct balance of nutrients to grow the food.

Also, there IS such thing as too much of a good thing.  If you simply use compost, it can contain too many specific minerals, which can cause issues.

Another problem that you can face with simply using compost to plant is that the roots of what you are often growing will have a more difficult time becoming established, and there are also issue with water retention.

Overall, it is not recommended just to use compost as the material to plant your food.

Do I Need to Use Fertilizer If I Use Compost?

Compost is considered to be a “soil amendment,” so it should not be used alone.  An excellent fertilizer to mix with your compost will ensure that you are offering the items you are growing the best nutrients available.

A couple of nutrients that fertilizer can add to your compost include magnesium and calcium. 

Fertilizers can be slow-releasing or fast releasing, so adding the right one for what you are attempting to achieve is essential to your success. 

Additionally, fertilizers can help to prevent specific issues or promote different things in compost.  Those things can range from avoiding worms, keeping rabbits out of your garden, to promoting large blooming.

A good fertilizer is an addition that should be considered for your composting projects. 

The Basics About Composting

Composting can be a complicated concept due to the multiple options and dos and don’ts involved in the process.  Doing a bit of research into what compost is, how it differs from the soil, and whether or not you will need a fertilizer are just a few things that should be considered before committing to how you plan to compost.

Check out our How To Begin Composting Guide for more detailed information.

Knowing that compost will eventually break down and turn into soil, deciding on the option of cold composting or hot composting is essential, especially if there is a time factor involved with the need for the compost to become soil more quickly.

Keeping in mind that you CAN have too much compost, having a balance between proper soil, fertilizer, and compost is essential to the success of your compost heap. 

All in all, if you are trying to decide to reduce your carbon footprint, become more self-sustained, and/or grow your own organic foods, proper composting is a great vehicle to make these things happen. 

Taking the plunge into composting does not have to be a foray into the unknown.  If you try one way of composting and it does not meet your needs, try combining some of the other tips and tricks until you find the right combination for you and your needs.

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